This document summarizes a study examining alternative trajectories for wheel loaders working in short loading cycles. It describes analyzing trajectories beyond the traditional V- or Y-cycle patterns. Different cycle variants were examined, including maintaining the classic cycle shape but varying parameters. The document outlines limitations in simplifying curves to circular arcs for analysis versus using clothoid curves. It also describes optimizing cycle parameters like reversing point angle and turning radii to minimize transport distance or time for given load receiver positions. The goal is to identify more efficient trajectories for applications like simulations, operator assistance, autonomous machines and hybrid energy management.
Simulating Operability of Wheel Loaders: Operator Models and Quantification o...Reno Filla
In this paper make the case that operability needs to be considered early on in the development of wheel loaders, alongside such established design targets as productivity and energy efficiency. We summarise research that shows how proper operator models can introduce a “human element” into dynamic simulations, providing more relevant answers with respect to operator-influenced complete-machine properties such as productivity and energy efficiency. We then show two ways of also drawing conclusions on the operability of wheel loaders by analysing either measurement data from physical tests or simulation results.
Evaluating the efficiency of wheel loader bucket designs and bucket filling s...Reno Filla
In this paper we outline how optimising bucket design and bucket filling is connected to improving the total energy efficiency of a wheel loader. Results from our work with particle simulations are shown and it is discussed that, while ideally such simulations should be coupled to models of the machine, operator and the work environment, it is nonetheless possible to simulate stand-alone and utilise simple performance indicators to compare different bucket designs and different bucket filling strategies in a reasonably fair manner. Suitable and less suitable performance indicators are derived and discussed in detail.
Alternative system solutions for wheel loaders and other construction equipmentReno Filla
- The document discusses alternative system solutions for wheel loaders and other construction equipment to reduce fuel consumption by 50% through hybrid technology.
- It analyzes wheel loaders as complex energy conversion systems and describes the key balances of force, motion, and power that must be maintained for high productivity, energy efficiency, and operability.
- Hybridization is proposed to maintain these balances through additional electric drive components that can assist both the hydraulic and drivetrain systems in parallel or series configurations.
Hybrid Power Systems for Construction Machinery: Aspects of System Design and...Reno Filla
This paper will examine the wheel loader as a system with two parallel energy conversion systems that show a complex interaction with each other and with the power source. Using a systematic design approach, several principle design solutions for hybridization can be found.
Furthermore, the human operator with his/her control actions needs to be considered as part of the total system. This paper will therefore also connect to results from ongoing and previous research into operator workload and operability.
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-51999
http://dx.doi.org/10.1115/IMECE2009-10458
Study of a method for assessing operability of working machines in physical a...Reno Filla
In this study of eighteen wheel loader operators, test-driving a machine in three different traction force settings, we found strong support for the hypothesis that the operator’s control commands can be used to assess the machine’s operability, at least in form of ease of bucket filling.
The methods chosen to derive the control effort worked well and were computationally efficient.
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-70392
A Methodology for Modeling the Influence of Construction Machinery Operators ...Reno Filla
This paper is concerned with modeling the actions of a human operator of construction machinery and integrating this operator model into a large, complex simulation model of the complete machine and its environment. Because human operators to a large degree affect how the machine is run, adaptive operator models are a necessity when the simulation goal is quantification and optimization of productivity and energy efficiency. Interview studies and test series have been performed to determine how professionals operate wheel loaders. Two models using different approaches were realized and integrated into a multi-domain model for dynamic simulation. The results are satisfactory and the methodology is easily usable for other, similar situations.
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-51998
http://dx.doi.org/10.1007/978-3-642-02809-0_65
Using Dynamic Simulation in the Development of Construction MachineryReno Filla
As in the car industry for quite some time, dynamic simulation of complete vehicles is being practiced more and more in the development of off-road machinery. However, specific questions arise due not only to company structure and size, but especially to the type of product. Tightly coupled, non-linear subsystems of different domains make prediction and optimisation of the complete system's dynamic behaviour a challenge. Furthermore, the demand for versatile machines leads to sometimes contradictory target requirements and can turn the design process into a hunt for the least painful compromise. This can be avoided by profound system knowledge, assisted by simulation-driven product development. This paper gives an overview of joint research into this issue by Volvo Wheel Loaders and Linköping University on that matter, lists the results of a related literature review and introduces the term "operability". Rather than giving detailed answers, the problem space for ongoing and future research is examined and possible solutions are sketched.
http://arxiv.org/abs/cs/0305036
An Event-driven Operator Model for Dynamic Simulation of Construction MachineryReno Filla
Prediction and optimisation of a wheel loader's dynamic behaviour is a challenge due to tightly coupled, non-linear subsystems of different technical domains. Furthermore, a simulation regarding performance, efficiency, and operability cannot be limited to the machine itself, but has to include operator, environment, and work task. This paper presents some results of our approach to an event-driven simulation model of a human operator. Describing the task and the operator model independently of the machine's technical parameters, gives the possibility to change whole sub-system characteristics without compromising the relevance and validity of the simulation.
http://arxiv.org/abs/cs/0506033
Simulating Operability of Wheel Loaders: Operator Models and Quantification o...Reno Filla
In this paper make the case that operability needs to be considered early on in the development of wheel loaders, alongside such established design targets as productivity and energy efficiency. We summarise research that shows how proper operator models can introduce a “human element” into dynamic simulations, providing more relevant answers with respect to operator-influenced complete-machine properties such as productivity and energy efficiency. We then show two ways of also drawing conclusions on the operability of wheel loaders by analysing either measurement data from physical tests or simulation results.
Evaluating the efficiency of wheel loader bucket designs and bucket filling s...Reno Filla
In this paper we outline how optimising bucket design and bucket filling is connected to improving the total energy efficiency of a wheel loader. Results from our work with particle simulations are shown and it is discussed that, while ideally such simulations should be coupled to models of the machine, operator and the work environment, it is nonetheless possible to simulate stand-alone and utilise simple performance indicators to compare different bucket designs and different bucket filling strategies in a reasonably fair manner. Suitable and less suitable performance indicators are derived and discussed in detail.
Alternative system solutions for wheel loaders and other construction equipmentReno Filla
- The document discusses alternative system solutions for wheel loaders and other construction equipment to reduce fuel consumption by 50% through hybrid technology.
- It analyzes wheel loaders as complex energy conversion systems and describes the key balances of force, motion, and power that must be maintained for high productivity, energy efficiency, and operability.
- Hybridization is proposed to maintain these balances through additional electric drive components that can assist both the hydraulic and drivetrain systems in parallel or series configurations.
Hybrid Power Systems for Construction Machinery: Aspects of System Design and...Reno Filla
This paper will examine the wheel loader as a system with two parallel energy conversion systems that show a complex interaction with each other and with the power source. Using a systematic design approach, several principle design solutions for hybridization can be found.
Furthermore, the human operator with his/her control actions needs to be considered as part of the total system. This paper will therefore also connect to results from ongoing and previous research into operator workload and operability.
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-51999
http://dx.doi.org/10.1115/IMECE2009-10458
Study of a method for assessing operability of working machines in physical a...Reno Filla
In this study of eighteen wheel loader operators, test-driving a machine in three different traction force settings, we found strong support for the hypothesis that the operator’s control commands can be used to assess the machine’s operability, at least in form of ease of bucket filling.
The methods chosen to derive the control effort worked well and were computationally efficient.
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-70392
A Methodology for Modeling the Influence of Construction Machinery Operators ...Reno Filla
This paper is concerned with modeling the actions of a human operator of construction machinery and integrating this operator model into a large, complex simulation model of the complete machine and its environment. Because human operators to a large degree affect how the machine is run, adaptive operator models are a necessity when the simulation goal is quantification and optimization of productivity and energy efficiency. Interview studies and test series have been performed to determine how professionals operate wheel loaders. Two models using different approaches were realized and integrated into a multi-domain model for dynamic simulation. The results are satisfactory and the methodology is easily usable for other, similar situations.
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-51998
http://dx.doi.org/10.1007/978-3-642-02809-0_65
Using Dynamic Simulation in the Development of Construction MachineryReno Filla
As in the car industry for quite some time, dynamic simulation of complete vehicles is being practiced more and more in the development of off-road machinery. However, specific questions arise due not only to company structure and size, but especially to the type of product. Tightly coupled, non-linear subsystems of different domains make prediction and optimisation of the complete system's dynamic behaviour a challenge. Furthermore, the demand for versatile machines leads to sometimes contradictory target requirements and can turn the design process into a hunt for the least painful compromise. This can be avoided by profound system knowledge, assisted by simulation-driven product development. This paper gives an overview of joint research into this issue by Volvo Wheel Loaders and Linköping University on that matter, lists the results of a related literature review and introduces the term "operability". Rather than giving detailed answers, the problem space for ongoing and future research is examined and possible solutions are sketched.
http://arxiv.org/abs/cs/0305036
An Event-driven Operator Model for Dynamic Simulation of Construction MachineryReno Filla
Prediction and optimisation of a wheel loader's dynamic behaviour is a challenge due to tightly coupled, non-linear subsystems of different technical domains. Furthermore, a simulation regarding performance, efficiency, and operability cannot be limited to the machine itself, but has to include operator, environment, and work task. This paper presents some results of our approach to an event-driven simulation model of a human operator. Describing the task and the operator model independently of the machine's technical parameters, gives the possibility to change whole sub-system characteristics without compromising the relevance and validity of the simulation.
http://arxiv.org/abs/cs/0506033
06-Traffic Characterization ( Highway and Airport Engineering Dr. Sherif El-B...Hossam Shafiq I
This document discusses traffic characterization and loadings for pavement design. It covers topics like vehicle characteristics, axle configurations, traffic composition, sources of traffic data, load equivalency factors, truck factors, and how to calculate estimated 18-kip equivalent single-axle loads (ESALs) using traffic data. The goal is to account for the full spectrum of traffic loads that pavement will experience over its design life when determining appropriate pavement thickness.
The document discusses planned upgrades to the oil water separator (OWS) and oily water transfer (OWT) systems on the LCC-19. It describes replacing the current C-50 OWS with a newer VS-50 model with improved separation efficiency. It also involves replacing aging OWT pumps with more reliable models and integrating all subsystem components through an automated control system. The upgrades aim to improve system performance, sustainability, and reduce maintenance costs through use of more durable parts and a simplified design. An engineering team validated ship diagrams to ensure accurate documentation of changes before fabricating new identification plates.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.t
The formula cars need high tire grip on racing challenge by reducing rolling displacement at corner or
double change lands. In this case study, the paper clarifies some issues related to suspension system with
inerter to reduce displacement and rolling angle under impact from road disturbance on Formula SAE
Car. We propose some new designs, which have an advance for suspension system by improving dynamics.
We optimize design of model based on the minimization of cost functions for roll dynamics, by reducing the
displacement transfer and the energy consumed by the inerter. Base on a passive suspension model that we
carried out quarter-car and half-car model for different parameters which show the benefit of the inerter.
The important advantage of the proposed solution is its integration a new mechanism, the inerter, this
system can increase advance in development and have effects on the vehicle dynamics in stability vehicle.
The document discusses plans to double the railway line between Utraitia and Zafrabad stations in Lucknow Division of Northern Railway. It will cost approximately 72 crores and involve doubling 12.5 km of track including 2 stations. Work will include expanding formations, bridges, adding ballast, installing new rails, sleepers, points and crossings, upgrading level crossings, and improving station buildings and platforms. Progress on related doubling projects is also provided, such as launching a girder at Anoopganj station in April 2015 and constructing an LHS at Faizabad using cut and cover method from July 15-20, 2015. Details of the current status of the project were obtained from the Northern Railway office in August
Virtual Durability Simulation for Chassis of Commercial vehicleIRJET Journal
1) The document presents a virtual simulation methodology to predict the fatigue durability of commercial vehicle chassis.
2) Road load data is collected from instrumenting a reference vehicle and conducting tests. This data is used to simulate multi-poster durability testing of the chassis through finite element analysis and multi-body dynamics.
3) The methodology accurately calculates stress histories and predicts critical failure locations, allowing virtual validation of the chassis design before physical testing. This reduces development time and costs.
IRJET - Analysis of Skew Bridge using Computational MethodIRJET Journal
The document analyzes skew bridges with different skew angles (0-60 degrees) and spans (16-24 meters) using the STAAD Pro software. It considers dead loads, live loads, and impact loads according to IRC and AASHTO standards. The analysis results in bending moments, torsion moments, shear forces, and deflections for T-beam girders. Guidelines are provided for grillage layout and load consideration in the analysis and design of skew bridges.
The document discusses plans to double an existing single railway line between Utraitia and Zafarabad in India. Doubling the line is needed due to increasing traffic volume that is straining the capacity of the existing line. It will allow more trains to operate and enable some traffic to be diverted from another heavily used route. The proposed doubling project would involve conducting surveys, acquiring additional land, expanding bridges and stations, and rebuilding the track bed to accommodate a second line. Completing this doubling is important to increase the overall capacity of the major rail corridor between Mughalsarai and Amritsar.
This document summarizes a technical paper about designing and tuning air suspensions for tractors. It discusses the challenges of achieving a balance between ride comfort and handling for tractor-trailer combinations, given their mass distribution and the influence of the trailer on dynamics. The paper presents the development of a new primary air suspension system for a Volkswagen tractor to improve comfort, protect fragile loads, and allow for different trailer configurations while maintaining other vehicle characteristics. A mixed suspension using springs in front and air bags in the rear was selected based on its benefits and ability to meet design goals. The tuning process and methods used to evaluate and optimize the suspension are also described.
This document discusses the factors that influence the acceleration of a gravity-powered "soapbox" vehicle without suspension. It presents a mathematical model that accounts for various resistive forces like rolling resistance. The analysis is based on a teaching model used to design actual soapbox cars for racing. A computer model was developed to study how design parameters like wheel diameter and mass affect acceleration. The goal is to maximize initial acceleration to reduce race time over a given track distance.
2012 SAE-A Young Engineer of the Year Award - Leaf Spring Simulation ToolMarwan Zogheib
Marwan Zogheib developed a Microsoft Excel-based tool to simulate the effect of vehicle installation on leaf spring characteristics for Toyota Technical Center Australia. The tool calculates wheel rate based on bench spring force-deflection measurements and accounts for the complex relationships between installation geometry and spring rate. Validation against physical vehicle measurements found average and maximum errors of 6.4% and 12.2% respectively. The tool allows designers to efficiently and accurately develop leaf springs to meet ride and handling targets, improving on previous iterative methods.
The document reports on a project to double a 10 km stretch of railway line between Shivnagar and Bandhuakalan. It discusses the objectives, methodology, location details, traffic survey results, specifications of work including earthwork, bridges, level crossings, track linking process, and conclusions. The doubling is aimed to ease mounting rail traffic pressure and allow optimal use of maintenance machines by providing an additional track on the busy single line section.
1) Researchers developed a Structural Health Index (SHI) to describe the structural integrity of pavements based on backcalculated layer moduli from falling weight deflectometer testing.
2) The SHI is calculated using a backcalculation software to determine layer moduli, which are then statistically modeled to produce an index from 0-100.
3) The SHI was validated and shown to realistically represent structural conditions, providing additional information to complement existing pavement management indices in identifying structurally deficient sections.
A presentation given at the SAE COMVEC conference this year during the CFD expert panel. Focuses on the new adjoint solver that is part of the automotive CFD suite, Elements, from Streamline Solutions.
Aerodynamic analysis and optimization of wind deflector in a Commercial load ...AM Publications
In the field of commercial goods transport, trucks have an important place. One of the main problems faced by truck manufacturers is the Air resistance associated with the highway running. Since trucks have a large frontal area and the presence of a trailer also leads to the truck experiencing significant resistance which has to be overcome. This can be reduced through the use of wind deflectors. A well-designed wind deflector can reduce wind resistance to a certain extent. Optimizing the angle of the wind deflector also causes reduced drag force acting on the vehicle, thereby reducing the fuel intake. Here the initial drag of 2050 N is reduced to 1688.453 N using a 1.75 m wind deflector at 45 degree angle resulting in the reduction of drag by 17.6%.
International Journal of Engineering Research and Development IJERD Editor
• Electrical, Electronics and Computer Engineering,
• Information Engineering and Technology,
• Mechanical, Industrial and Manufacturing Engineering,
• Automation and Mechatronics Engineering,
• Material and Chemical Engineering,
• Civil and Architecture Engineering,
• Biotechnology and Bio Engineering,
• Environmental Engineering,
• Petroleum and Mining Engineering,
• Marine and Agriculture engineering,
• Aerospace Engineering.
This presentation contains:
1. Types of FLT
2. Specifications of FLT
3. Capacity rating of FLT
4. Turning Radius and Aisle Width
5. FLT Attachments
6. Power Rating Calculations for FLT
7. Battery rating & Selection
8. Energy calculation
Find Lecture Videos on my youtube channel -> https://www.youtube.com/channel/UC1mGQxcNkyUjoQIYZaSFtPQ?view_as=subscriber
11-Structural Design ( Highway Engineering Dr. Sherif El-Badawy )Hossam Shafiq I
The document discusses various methods for flexible pavement design, including empirical, mechanistic, and mechanistic-empirical methods. It provides details on the AASHTO, Asphalt Institute, and MEPDG design methods, including required inputs like traffic, materials properties, and environmental factors as well as outputs like structural number and layer thicknesses. It also explains concepts fundamental to flexible pavement design like structural number, layer coefficients, serviceability, reliability, and distresses like rutting and cracking.
Thank you for the presentation. I appreciate you sharing insights into Volvo's vision and work on construction equipment design. Please let me know if you have any other questions.
A 3tons payload front end articulated loader with a 150HP cummins engine and 1.76 to 3M3 bucket. The wheel loader is a brute powered that performs efficiently with low fuel intake.
Electromobility and Construction MachineryReno Filla
The search for energy efficient solutions goes on also for construction machinery, and hybrids are a given topic. This seminar looks at related research and pre-development at Volvo Construction Equipment and focuses on wheel loaders. In these machines, drive train and hydraulics are both equally powerful and compete for the limited engine torque. There is a large theoretic potential for the increase of energy efficiency, but to leverage this, a holistic approach is needed. The wheel loader is examined as a system with drive train and hydraulics as two parallel energy conversion systems that show a complex interaction with each other and the power source. Using a systematic design approach, several principle design solutions for hybridization can be found and are discussed.
06-Traffic Characterization ( Highway and Airport Engineering Dr. Sherif El-B...Hossam Shafiq I
This document discusses traffic characterization and loadings for pavement design. It covers topics like vehicle characteristics, axle configurations, traffic composition, sources of traffic data, load equivalency factors, truck factors, and how to calculate estimated 18-kip equivalent single-axle loads (ESALs) using traffic data. The goal is to account for the full spectrum of traffic loads that pavement will experience over its design life when determining appropriate pavement thickness.
The document discusses planned upgrades to the oil water separator (OWS) and oily water transfer (OWT) systems on the LCC-19. It describes replacing the current C-50 OWS with a newer VS-50 model with improved separation efficiency. It also involves replacing aging OWT pumps with more reliable models and integrating all subsystem components through an automated control system. The upgrades aim to improve system performance, sustainability, and reduce maintenance costs through use of more durable parts and a simplified design. An engineering team validated ship diagrams to ensure accurate documentation of changes before fabricating new identification plates.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.t
The formula cars need high tire grip on racing challenge by reducing rolling displacement at corner or
double change lands. In this case study, the paper clarifies some issues related to suspension system with
inerter to reduce displacement and rolling angle under impact from road disturbance on Formula SAE
Car. We propose some new designs, which have an advance for suspension system by improving dynamics.
We optimize design of model based on the minimization of cost functions for roll dynamics, by reducing the
displacement transfer and the energy consumed by the inerter. Base on a passive suspension model that we
carried out quarter-car and half-car model for different parameters which show the benefit of the inerter.
The important advantage of the proposed solution is its integration a new mechanism, the inerter, this
system can increase advance in development and have effects on the vehicle dynamics in stability vehicle.
The document discusses plans to double the railway line between Utraitia and Zafrabad stations in Lucknow Division of Northern Railway. It will cost approximately 72 crores and involve doubling 12.5 km of track including 2 stations. Work will include expanding formations, bridges, adding ballast, installing new rails, sleepers, points and crossings, upgrading level crossings, and improving station buildings and platforms. Progress on related doubling projects is also provided, such as launching a girder at Anoopganj station in April 2015 and constructing an LHS at Faizabad using cut and cover method from July 15-20, 2015. Details of the current status of the project were obtained from the Northern Railway office in August
Virtual Durability Simulation for Chassis of Commercial vehicleIRJET Journal
1) The document presents a virtual simulation methodology to predict the fatigue durability of commercial vehicle chassis.
2) Road load data is collected from instrumenting a reference vehicle and conducting tests. This data is used to simulate multi-poster durability testing of the chassis through finite element analysis and multi-body dynamics.
3) The methodology accurately calculates stress histories and predicts critical failure locations, allowing virtual validation of the chassis design before physical testing. This reduces development time and costs.
IRJET - Analysis of Skew Bridge using Computational MethodIRJET Journal
The document analyzes skew bridges with different skew angles (0-60 degrees) and spans (16-24 meters) using the STAAD Pro software. It considers dead loads, live loads, and impact loads according to IRC and AASHTO standards. The analysis results in bending moments, torsion moments, shear forces, and deflections for T-beam girders. Guidelines are provided for grillage layout and load consideration in the analysis and design of skew bridges.
The document discusses plans to double an existing single railway line between Utraitia and Zafarabad in India. Doubling the line is needed due to increasing traffic volume that is straining the capacity of the existing line. It will allow more trains to operate and enable some traffic to be diverted from another heavily used route. The proposed doubling project would involve conducting surveys, acquiring additional land, expanding bridges and stations, and rebuilding the track bed to accommodate a second line. Completing this doubling is important to increase the overall capacity of the major rail corridor between Mughalsarai and Amritsar.
This document summarizes a technical paper about designing and tuning air suspensions for tractors. It discusses the challenges of achieving a balance between ride comfort and handling for tractor-trailer combinations, given their mass distribution and the influence of the trailer on dynamics. The paper presents the development of a new primary air suspension system for a Volkswagen tractor to improve comfort, protect fragile loads, and allow for different trailer configurations while maintaining other vehicle characteristics. A mixed suspension using springs in front and air bags in the rear was selected based on its benefits and ability to meet design goals. The tuning process and methods used to evaluate and optimize the suspension are also described.
This document discusses the factors that influence the acceleration of a gravity-powered "soapbox" vehicle without suspension. It presents a mathematical model that accounts for various resistive forces like rolling resistance. The analysis is based on a teaching model used to design actual soapbox cars for racing. A computer model was developed to study how design parameters like wheel diameter and mass affect acceleration. The goal is to maximize initial acceleration to reduce race time over a given track distance.
2012 SAE-A Young Engineer of the Year Award - Leaf Spring Simulation ToolMarwan Zogheib
Marwan Zogheib developed a Microsoft Excel-based tool to simulate the effect of vehicle installation on leaf spring characteristics for Toyota Technical Center Australia. The tool calculates wheel rate based on bench spring force-deflection measurements and accounts for the complex relationships between installation geometry and spring rate. Validation against physical vehicle measurements found average and maximum errors of 6.4% and 12.2% respectively. The tool allows designers to efficiently and accurately develop leaf springs to meet ride and handling targets, improving on previous iterative methods.
The document reports on a project to double a 10 km stretch of railway line between Shivnagar and Bandhuakalan. It discusses the objectives, methodology, location details, traffic survey results, specifications of work including earthwork, bridges, level crossings, track linking process, and conclusions. The doubling is aimed to ease mounting rail traffic pressure and allow optimal use of maintenance machines by providing an additional track on the busy single line section.
1) Researchers developed a Structural Health Index (SHI) to describe the structural integrity of pavements based on backcalculated layer moduli from falling weight deflectometer testing.
2) The SHI is calculated using a backcalculation software to determine layer moduli, which are then statistically modeled to produce an index from 0-100.
3) The SHI was validated and shown to realistically represent structural conditions, providing additional information to complement existing pavement management indices in identifying structurally deficient sections.
A presentation given at the SAE COMVEC conference this year during the CFD expert panel. Focuses on the new adjoint solver that is part of the automotive CFD suite, Elements, from Streamline Solutions.
Aerodynamic analysis and optimization of wind deflector in a Commercial load ...AM Publications
In the field of commercial goods transport, trucks have an important place. One of the main problems faced by truck manufacturers is the Air resistance associated with the highway running. Since trucks have a large frontal area and the presence of a trailer also leads to the truck experiencing significant resistance which has to be overcome. This can be reduced through the use of wind deflectors. A well-designed wind deflector can reduce wind resistance to a certain extent. Optimizing the angle of the wind deflector also causes reduced drag force acting on the vehicle, thereby reducing the fuel intake. Here the initial drag of 2050 N is reduced to 1688.453 N using a 1.75 m wind deflector at 45 degree angle resulting in the reduction of drag by 17.6%.
International Journal of Engineering Research and Development IJERD Editor
• Electrical, Electronics and Computer Engineering,
• Information Engineering and Technology,
• Mechanical, Industrial and Manufacturing Engineering,
• Automation and Mechatronics Engineering,
• Material and Chemical Engineering,
• Civil and Architecture Engineering,
• Biotechnology and Bio Engineering,
• Environmental Engineering,
• Petroleum and Mining Engineering,
• Marine and Agriculture engineering,
• Aerospace Engineering.
This presentation contains:
1. Types of FLT
2. Specifications of FLT
3. Capacity rating of FLT
4. Turning Radius and Aisle Width
5. FLT Attachments
6. Power Rating Calculations for FLT
7. Battery rating & Selection
8. Energy calculation
Find Lecture Videos on my youtube channel -> https://www.youtube.com/channel/UC1mGQxcNkyUjoQIYZaSFtPQ?view_as=subscriber
11-Structural Design ( Highway Engineering Dr. Sherif El-Badawy )Hossam Shafiq I
The document discusses various methods for flexible pavement design, including empirical, mechanistic, and mechanistic-empirical methods. It provides details on the AASHTO, Asphalt Institute, and MEPDG design methods, including required inputs like traffic, materials properties, and environmental factors as well as outputs like structural number and layer thicknesses. It also explains concepts fundamental to flexible pavement design like structural number, layer coefficients, serviceability, reliability, and distresses like rutting and cracking.
Thank you for the presentation. I appreciate you sharing insights into Volvo's vision and work on construction equipment design. Please let me know if you have any other questions.
A 3tons payload front end articulated loader with a 150HP cummins engine and 1.76 to 3M3 bucket. The wheel loader is a brute powered that performs efficiently with low fuel intake.
Electromobility and Construction MachineryReno Filla
The search for energy efficient solutions goes on also for construction machinery, and hybrids are a given topic. This seminar looks at related research and pre-development at Volvo Construction Equipment and focuses on wheel loaders. In these machines, drive train and hydraulics are both equally powerful and compete for the limited engine torque. There is a large theoretic potential for the increase of energy efficiency, but to leverage this, a holistic approach is needed. The wheel loader is examined as a system with drive train and hydraulics as two parallel energy conversion systems that show a complex interaction with each other and the power source. Using a systematic design approach, several principle design solutions for hybridization can be found and are discussed.
In working machines like wheel loaders the human operator is essential for the performance of the total system. Productivity and energy efficiency are both dependent not only on inherent machine properties and working place conditions, but also on how the operator manoeuvres the machine. In order to operate energy-efficient the operator has to experience the machine as harmonic. This is important to consider during the development of such working machines.
The influence of the human operator is an aspect that is traditionally neglected in dynamic simulations conducted in concept design, because the modelling needs to be extended beyond the technical system. In the research presented in this paper we show two approaches to rule-based simulation models of a wheel loader operator. Both operator models interact with the machine model just as a human operator does with the actual machine. It is demonstrated that both operator models are able to adapt to basic variations in workplace setup and machine capability. A "human element" can thus be introduced into dynamic simulations of working machines, providing more relevant answers with respect to operator-influenced complete-machine properties such as productivity and energy efficiency.
Operability of a machine is traditionally evaluated by professional test operators using physical prototypes. The presented research demonstrates how this can be complemented by a calculated measure for the operator’s control effort, derived from the recorded control commands of the machine operator. This control effort measure can also be calculated from the control commands of an operator model in a simulation, such as those presented here. It thus also allows for an assessment of operability already in the concept design phase.
A study to compare trajectory generation algorithms for automatic bucket fill...Reno Filla
In this paper we study how automatic bucket filling can be realised in wheel loaders. Based on observations of how experienced operators use their machines in bucket applications, four algorithms for parametric generation of bucket trajectories are investigated. The algorithms have been developed and tuned using a simplistic static integration-based approach.
The Discrete Element Method is used to validate the predictive capability of the aforementioned algorithms. Results and limitations of the simplistic approach in comparison to the numerical results, as well as specific simulation-related challenges and findings are reported and discussed.
65% of online shop visitors leave during checkout without completing a purchase. To increase sales, shop owners should optimize the checkout process, offer more payment options, and re-engage with visitors who leave the site through remarketing ads or emails reminding them of abandoned carts. Display advertising can also be effective for generating new traffic and retargeting past visitors if campaigns are properly targeted, transparent, and avoid spamming users.
Rainy river site visit presentation v finalnewgold2011
The document provides details about a site visit to the Rainy River gold mine project in Ontario, Canada. It includes:
- An agenda for the site visit with presentations on geology, development plans, operations, and life of mine planning.
- An overview of the Rainy River project including reserves, production targets, costs, and timeline.
- Details on funding for the project including proceeds from a streaming deal and the project's financial analysis.
The document discusses construction productivity measurement and benchmarking. It defines productivity and explains why it is important, especially for the construction industry. Some key factors affecting construction labor productivity are identified. The document also discusses quality and its relationship to productivity. Various methods for improving productivity are outlined. Productivity calculation and benchmarking models and their application to the construction industry are explained. Labor productivity studies comparing different regions in India and internationally are summarized.
GEORGE ZIMMERMAN & EBOLA CRISIS (Russian)VogelDenise
Какова связь между Джорджем Циммерман и Эбола Outbreak / Кризис в Африке? Это кажется более расистских нападений со стороны Соединенных Штатов режима деспотизма Америки, который контролируется евреями и превосходства белой расы!
The document discusses different types of observation techniques used in research. It describes six types of observations: structured observation, unstructured observation, participant observation, non-participant observation, controlled observation, and uncontrolled observation. Each type is explained along with its merits and demerits. The document also covers advantages and disadvantages of using observation methods in research.
GEORGE ZIMMERMAN & EBOLA CRISIS (Czech)VogelDenise
Spojení mezi Spojenými státy americkými, rasismu a Ebola!
Jaká je souvislost mezi George Zimmerman a ebola Outbreak / krize v Africe? Zdá se, VÍCE rasistických útoků ze strany Spojených států amerických v despotismu režimu, který je ovládán Židy a nadřazenost bílé rasy!
Co je tak smutné, je skutečnost, že klamavým praktikám Spojených států amerických, Izraele a jejich spojenci jsou příčinou genocidy praktiky pomocí Ebola NEMOC!
Zajímavý je, jak se Ebola nemoc nerozšířila ve Spojených státech amerických, i když těch údajně INFIKOVANÝ přišli do kontaktu s mnoha a YES, tělesné tekutiny byly přítomny. CO hanba a hanbou!
Je to škoda a ostuda afričtí lídři se zdají být neznalý se skutečností, které Spojené státy, Izrael a jejich WHITE spojenec Protipóly chtějí mít přístup k jejich půdu a přírodní zdroje - tedy hledá se zabít je pryč a / nebo je umístit na plantážích!
Kementerian Pendidikan bertanggung jawab untuk melaksanakan penelitian, sosialisasi, dan koordinasi kegiatan terkait pendidikan, serta mengelola staf ahli dan direktorat jenderal di bawah naungan kementerian.
This document discusses a motion filed by Creditor Vogel Newsome regarding the bankruptcy case of Ladye M. Townsend. Newsome argues the bankruptcy court lacks jurisdiction over the matter as her prior federal lawsuit against Townsend in district court established that court's jurisdiction. Newsome also alleges misconduct by Townsend's attorney and moves for Rule 11 sanctions. Newsome consolidates her various motions and does not waive her defense that the bankruptcy court lacks jurisdiction.
The document summarizes multifamily real estate market performance in the second quarter of 2012. Key points include:
- Occupancy and rent growth remained strong across most markets, fueled by economic challenges encouraging renting over homeownership.
- Transaction volume was robust, totaling $23 billion at mid-year and keeping pace with 2005 levels.
- Competition for assets pushed investors to seek higher yields in secondary and tertiary markets through value-add strategies.
- The outlook anticipates continued strong performance over the next 24 months before slowing as housing challenges are resolved.
The document summarizes planned improvements to East Park Reservoir in the city. The reservoir was originally constructed in 1869 following a drought. It will now be upgraded with two new 400-foot diameter concrete water storage tanks to replace aging infrastructure and protect water quality for many decades to come. Construction will take place primarily within the existing berm and last around 3.5 years, with some short-term external work requiring traffic mitigation. Community input has been incorporated into the design.
Towards Finding the Optimal Bucket Filling Strategy through SimulationReno Filla
The purpose of earth-moving equipment like wheel loaders is to engage with the ground or other material. It is therefore obvious that the bucket filling phase must be included when studying optimal machine control over a complete working cycle because total productivity and efficiency of the machine are to a large extent determined by it. This paper reports and discusses the results of research into how to utilize Discrete Element Method simulations in combination with Optimal Control to find the optimal bucket filling strategy and what has been learned regarding preparing and conducting both simulations of bucket filling and physical testing for verification. This paper also discloses which bucket filling strategy appears to be optimal, based on the results so far – and why we cannot be completely certain.
A Case Study on Quantifying the Workload of Working Machine Operators by Mean...Reno Filla
This study examined operator workload in 18 wheel loader operators using psychophysiological measurements under different machine settings that limited engine speed and traction force. The findings did not support using these measurements to easily assess operator workload for machine testing, as other factors strongly influence workload. While workload-adaptive assistance could help with complex machines, different workload measurements may be needed for practical use by test engineers. The machine settings aimed to study the impact of limited traction force on workload during bucket filling, which requires simultaneously controlling multiple motions and is the most fuel-consuming part of the loading cycle. However, the results indicated operability is affected by many other machine and task factors beyond the settings tested.
A thesis update covering a process for deriving a gain-scheduled nonlinear controller for the motion control of an underwater vehicle, specifically an underwater buoyancy glider.
Robust control strategies for an electric motor driven accumulator with elast...ISA Interchange
This document discusses robust control strategies for an electric motor driven accumulator used in industrial web processing. It first presents a nonlinear model of the accumulator dynamics, including web tension, velocity, and carriage motion. It then linearizes the model around a working point for frequency analysis. Finally, it compares multi-model PI and H1 controllers for the accumulator, finding that both allow good robustness against mechanical parameter variations.
Reconstruction of globoidal cam follower motion curve based on B-splineIJRES Journal
Due to the development of the CNC technology, manufacturing the complex surface is becoming
more and more easier. Globoidal cam is an important part of intermittent motion mechanism, so nowadays
machining the globoidal cam by CNC machine is a new research area. In general, the contour line of the
globoidal cam can be described by the follower motion curve. But because of the property of the globoidal
cam, its contour surface is non-development, so the follower motion curve cannot defined by mathematical
expression. In order to solve this problem, this paper attempts to reconstruct the follower motion curve based on
B-spline by the help of MATLAB. In this research, 3 common follower motion laws are discussed: modified
constant velocity, modified trapezoid and modified sine. By observing the results, it can be said that
reconstruction of the follower motion curve is similar to the original curve which defined by mathematical
equation.
Dynamical modelling of the excavating chain of a ballast cleaning machineIJERA Editor
The ballast bed as part of the railway track fulfils the important functions as the binding element
between sleepers and substructure. Fouling increases over the years for various reasons. When the necessary
good functioning is no longer assured, ballast bed cleaning must be performed. The machines, that perform that
task, are equipped with various complex mechanics - hydraulic systems that ensure high productivity,
efficiency and quality of the works. In this article is presented one way of studying the work of the machine for
excavating ballast from the ballast bed to the sieving machine. We suggest a dynamic model for simulating the
work of a scraper chain of a ballast cleaning machine with different working parameters.
Energy-Efficient Driving in the Portuguese Rail Operation (MSc. Dissertation ...João Vieira
The main share of energy consumption in railways consists of traction energy, i.e., energy required to move the trains. The amount of energy consumed is much influenced by the way the train is driven within schedule. As each driver has its own driving style and since the deduction of the energy-efficient driving strategy is not trivial, there are now available Driving Advice Systems to assist drivers in choosing the most energy-efficient actions.
The aim of this study was to develop an energy-efficient driving model in order to derive, for a given route and running time, an energy-efficient speed profile. The driving model was used to build efficient driving strategies for regional and inter-regional rail services in the Douro line. The model’s energy saving potential evaluation was done by using a train-running simulator in order to compare the driver’s actions and speed profiles of real cases with the most efficient driving strategies for the same situations. The simulation results point to an energy saving potential between 11 and 15%, just by changing the driving style.
Finally, a Driver Advice System prototype was developed, in order to assist the driver in adopting an efficient driving strategy. The prototype has been developed for the Android platform, to be implemented in a low-cost equipment, such as a tablet, equipped with GPS receiver.
Development and Implementation of a Washout Algorithm for a 6-dof Motion Plat...IJRES Journal
Flight simulators for pilot training is extremely important due safety and economic factors.
Flight simulator needs to simulate different kinds of complicated motion state such as roll, pitch and yaw
angles. It has six-degree of freedom, high precision, high rigid, modular design and many other advantages. The
motion system responds to the aircraft linear and angular accelerations in order to compute the most
appropriate cabin motion to replicate these accelerations, subject to the displacement limits and the velocity
limits of the actuators. The cabin accelerations are filtered in order to compute the most appropriate cabin
motion to replicate the actual airplane accelerations. This paper developed and implemented a motion washout
algorithm that can enhance the fidelity of motion platform and the cabin motion never exceeds the mechanical
limits of the motion platform, particularly the maximum actuator displacements and the maximum actuator
velocities.
Design, Simulation & Optimization of Gravity Spiral Roller Conveyer with Auto...IRJET Journal
The document describes the design, simulation and optimization of a vertical gravity spiral roller conveyor system with an automatic collision avoidance system for transporting boxes between 5 floors of a building. Key aspects include:
1. Designing the helical angle, roller assembly, frame and other parts using CAD software and analyzing them through finite element analysis for strength and modal properties.
2. Optimizing the design for weight reduction and cost effectiveness while maintaining required strength and durability.
3. Developing an automatic collision avoidance system using ultrasonic sensors and an Arduino board to prevent collisions between boxes entering and exiting each floor.
Ride comfort and handling of off-road vehicles can be significantly improved by replacing the normal passive dampers in the vehicle suspension system with controllable Semi-active dampers. The semi-active damping control system with variable shock absorber is widely used to improve the vehicle dynamic characteristics such as ride comfort and driving safety. To achieve better vehicle performance, the shock absorber with wide range of damping force variation develops. This is practically achieved by external valve control by manually. The performance of the semi-active shock absorber is investigated by single degree freedom (quarter vehicle model) test rig.
- Researchers at Université Clermont Auvergne developed a mechanical model of pitch control for an all-terrain automated guided vehicle (AGV) called RobCat during ballistic phases such as jumping.
- They conducted experiments on a test bench where RobCat was suspended by a transverse axis through its center of mass to validate the model. RobCat was tested with both its original hollow rubber tires and solid wheels with equivalent inertial parameters.
- The results supported the model of angular momentum conservation and showed that RobCat's orientation during an airborne phase can be controlled by accelerating or braking its wheels, demonstrating the feasibility of pitch control for the vehicle.
Introduced gearless power transmission arrangement used for skew shafts. In this transmission system no. of pins or links used must be odd..3,5,7,9…..& centers of any two pins or links hole must not be on that line which represent the diameter of the shaft. If more pins or links used motion will be smoother, but increase in no. of pins or links not at the cost of strength of the shaft. Pins or links are fixed (may be permanent of temporary) in the drilled holes at the both shaft ends due to which motion is transferred. The dimensions of the pins or links and angle for the pins are all given very precisely, holes drilled very accurately.
Proposed arrangement used for skew shafts at any angle & if there is a need we can change the angle between shafts during motion or during intermittent motion with any profile of shafts having rotational motion along its own axis. The Working of this arrangement is very smooth & use very effectively with a very minimum amount of power losses.
Hydrostatic Continuous Variable Power Transmission Drive for Two wheelers usi...ijsrd.com
Power transmission is an extremely important factor for the automotive industry today. In vehicles, the power transmission system is the major source of energy losses. This is an intentionally compact review for a module addressing basic Fluid Mechanics for incompressible fluids within the context of Applied Energy Systems. Rather than attempting to cover Fluid Mechanics in a very broad and general way, two practical areas are selected in the use of fluids, hydrostatic power transmission systems and the flow of fluids through pipes and fittings. Thus readers are prepared for applying the same and similar principles to a much broader range of practical applications in the future. The present review work relates to a rotary pump and motor transmission system, which permits a change in ratio between the speed of the driver and driven shafts from direct drive to neutral position. This transmission, which may be adopted for many uses, such as vehicles and machine tools, is endowed with the utmost ease of operation even under load, is of a simple and rugged construction and offers safety of operation even after an extended use.
Cfd study of a Pelton turbine runner by M.Minozzo R.Bergamin M.Merelli M.Galb...TUM
This document compares two computational fluid dynamics (CFD) approaches - traditional Eulerian and novel Lagrangian Moving Particle Simulation (MPS) - for simulating Pelton turbine runners. The traditional Eulerian approach requires significant geometry simplification and simulation time. The novel MPS approach can simulate the entire turbine geometry without simplification in less time. It also provides new insights not previously discovered, such as jet-jet interactions, opening possibilities for further optimization. Both approaches produce results within 1% of theoretical values, but MPS saves considerable time and resources.
This document discusses the optimization of hydro-mechanical power split transmissions. It begins by providing background on continuously variable transmissions and why hydro-mechanical power split transmissions are promising. It then describes the optimization problem as designing the transmission to maximize average efficiency by selecting displacements of the hydraulic machines and gear ratios. An optimization algorithm using particle swarm methods is used to solve this problem. Finally, the optimization method will be applied to study transmissions for a compact loader and agricultural tractor.
This document provides guidance on calculating bearing life for railway applications. It discusses calculation principles, basic rating life calculations according to ISO 281, and more advanced SKF rating life calculations. It also provides example calculations for typical symmetrical and link arm axlebox designs, showing how to determine static and dynamic bearing loads based on vehicle specifications in order to calculate the basic or SKF rating life in millions of revolutions or kilometers.
This document discusses concepts of mobility for mobile robot vehicles. It begins by introducing the configuration space (C-space) and task space for different types of vehicles including trains, hovercrafts, helicopters, aircraft, underwater robots, and cars. It describes vehicles as having different numbers of degrees of freedom and actuators, and whether they are fully or under-actuated. Common vehicles like cars are described as non-holonomic systems that cannot directly move between configurations but must follow paths. The document then focuses on modeling a car-like vehicle using the bicycle model, describing its kinematic equations of motion and non-holonomic constraint.
This document proposes a modified crawl gait technique for quadruped robots to achieve omnidirectional walking with increased stability compared to conventional methods. The conventional crawl gait has a stability margin of zero for some steps, making it unstable. The modified technique plans leg sequences and motions to maintain a positive stability margin at all times. It formulates the relationships between stability margin, stride length, and duty factor. Computer simulations and experiments on an actual quadruped robot validate that the modified crawl gait realizes omnidirectional walking with improved stability over uneven terrain.
This document discusses mobile robot vehicles and provides several examples of different types of mobile robot platforms. It covers key concepts related to mobility including configuration space, task space, degrees of freedom, and actuation. Examples discussed include trains, hovercrafts, helicopters, fixed-wing aircraft, underwater robots, and cars. Each example describes the robot's configuration space, degrees of freedom, actuation, and task space. The document aims to explain the basic issues involved in programming robots to perform tasks by analyzing different types of mobile robot platforms and their mobility characteristics.
Investigation on Chassis Dynamometer with Capability to Test Regenerative Bra...IJPEDS-IAES
An investigation-based approach to a bidirectional power flow method for
testing regenerative braking function on a chassis dynamometer is presented.
The requirements and specifications for capability to test regenerative
braking function of Electric Vehicle (EV) emulated by using a bidirectional
chassis dynamometer are discussed. The dynamometer emulates road load
conditions during testing, and regenerative braking is able to test their
function while the vehicle is in deceleration condition. Performances of
power requirement are illustrated and translated into sequence diagram. It is
shown that the proposed topology is particularly advantageous in generating
and regenerating power for energy consumption. The overview of
conventional chassis dynamometer and the proposed chassis dynamometer is
compared to investigate the parameter in the development of regenerative
braking test.
Similar to Optimizing the trajectory of a wheel loader working in short loading cycles (20)
In support of removal of periodic calibration of Flight RecordersReno Filla
This is not a Position Paper on Periodic Pressure Altitude Calibration of FR.
This is a paper on why the above is not needed.
This document will not contain a technical discussion of if, how, why and when the accuracy of pressure sensors in Flight Recorders possibly deviates and whether it then varies with absolute altitude, calendar age, frequency of use or some other variable.
We will not present statistical evidence for either occurrence or non-occurrence of "drifting" of pressure readings. Nobody has these data anyway.
What we will do in this document is to deliberate why we in our sport measure altitude to begin with and what the “good enough” level of accuracy is. From there we will examine how this can be achieved in FAI's legal framework and address possible needs for adjustment of the Sporting Code, if necessary at all.
Spoiler alert: the conclusion will be that unlike regularly visiting a dentist, periodically having to calibrate the pressure sensor in your Flight Recorder is not actually good for you. It is at best an expensive nuisance and if we can get by without this recurring hassle then we all are off for the better.
Brave new electric world: will hydraulics survive and who needs hydraulics anyway? A provocation delivered by an unsentimental system integrator. A real engineer doesn't "love" or "hate" but makes balanced and well-considered technology decisions based on performance, efficiency, application, quality, robustness, cost, etc.
Reflections on Research (and a Fractal Perspective on Systems Engineering)Reno Filla
This round-kick presentation for the 2022 LINK-SIC workshop (https://liu.se/en/article/link-sic-workshop-2022) spans the arc from research and predevelopment to knowledge in general (vs belief and opinion), systems engineering and the ongoing specialization/fragmentation of engineering , uncertainty, the climate-change related challenges ahead - and more.
This document summarizes Reno Filla's presentation on electric roads (e-roads) and the experience from pilot projects in Germany and Sweden. It discusses the power requirements for electric trucks, including 250-300 kW for constant speed driving and additional 120 kW per 1% grade. It also notes challenges like adaptive driver assistance systems in certain weather conditions and catenary interruptions. The presentation evaluates having enough power capacity for varying operating conditions and argues that 250 kW per truck is not over-dimensioned given power needs for acceleration, battery charging, and only partial road electrification.
SEC lecture "Electrification of Future Transports"Reno Filla
The document discusses the electrification of future transports. It notes the four main drivers of sustainable transport as congestion, pollution, energy security, and climate change. Scania is a leading provider of transport solutions and is working with partners and customers to drive the shift towards a more sustainable transport system. The presentation outlines Scania's goals to cut emissions from its operations and products by 2025 to help fuel the transition to more sustainable options.
Presentation for graduate students: Zoom in to learn the basics and refine your knowledge, then zoom out for perspective and to make connections. Then repeat until convergence. Which you might attain until the next disruption. ;-)
Der Diplom-Ingenieur Reno Filla ist verheiratet und hat ein Kind. Nach seinem Abschluss 1998 an unserer Hochschule ging er zu Volvo nach Schweden, wo er bis heute mit seiner Familie lebt. Seine Freizeit verbringt er gerne mit Segelfliegen. Über seine Zeit des Studiums und sein Werdegang nach dem Studium berichtet er uns in diesem Interview.
https://www.hs-magdeburg.de/hochschule/einrichtungen/alumni-management/interviews.html
Keynote presentation held at the 15th Scandinavian International Conference on Fluid Power 2017 in Linköping, Sweden
It covers the topics energy efficiency, electromobility, operator assistance, automation, connectivity and site solutions.
Towards Finding the Optimal Bucket Filling Strategy through SimulationReno Filla
The document discusses using simulation to find the optimal bucket filling strategy for a construction vehicle. It analyzed 5781 trajectories with 5 different filling strategies (labeled A through E) through discrete element method simulation. Various problems were encountered in the simulations, such as particles jumping unpredictably and large upward forces on the bucket, and solutions were developed to address them, such as adjusting the time step or adding more particle layers. Overall strategy A seemed most efficient while B was very inefficient. The analysis noted several important factors that were not captured in the simulations, such as the full loading cycle and stability of the vehicle, and suggested coupled large-scale simulation and optimization of the machine, environment, and operator may be needed to fully address finding the optimal strategy
Gliding Contest Scoring: current and proposal 8.1.4 for the 2016 IGC plenaryReno Filla
This is a supporting presentation to explain how scoring currently works (visualizing the official equations in a rearranged way) and what the effect of Dutch proposal 8.1.4 will be
For the joint IQPC Conferences "Automation & Connectivity for Mobile Machinery" and "HMI for Mobile Machinery", for which I also had the honor to serve as the conference chairman.
Selecting representative working cycles from large measurement data setsReno Filla
1. The document describes three methods for selecting representative work cycles from large datasets of machine usage data: the Mean Cycle Method, Synthetic Mean Method, and Least Error Method.
2. The Mean Cycle Method constructs an average cycle and selects the measured cycle closest to it. The Synthetic Mean Method constructs a cycle based on peak frequencies and amplitudes and selects the closest measured cycle. The Least Error Method compares all cycles and selects the one with the smallest deviations.
3. When tested on 100 wheel loader work cycles, the three methods produced similar but not identical results for the most representative cycle depending on the signals considered. Considering multiple important signals led to more agreement between the methods.
Fuel efficiency in construction equipment – optimize the machine as one systemReno Filla
In order to further optimize the fuel efficiency and productivity of construction equipment, 3 main potentials have been identified:
• job site optimization
• machine use optimization
• machine optimization
The focus of this paper is the machine optimization on the example of a wheel loader.
Optimizing losses in individual components must be done, but it will not be a game changer for fuel efficiency improvement. Three areas for promising improvement potentials:
• Optimizing the systems interactions
• Decoupling of systems
• Reduction of losses
One example is shown for a total machine optimization approach: the “Reverse by Braking” function is using the machine operating brakes to slow down the machine during power shuttle instead of using the engine power.
Decoupling of systems requires continuously variable transmission (CVT) functionality for the driveline. This can be achieved with hydraulic or electric CVTs. Two examples for decoupling systems are shown: the Volvo hydrostatic powersplit CVT prototype and a series hybrid wheel loader.
Further future potentials are explored, while the driveline and hydraulic technology are the enablers for drastic improvements: electrified site, plug in hybrid, alternative fuels, and new machine concepts.
Classification of physiological signals for wheel loader operators using Mult...Reno Filla
This summarizes a research paper that presents a classification approach called MMSE-CBR to classify physiological parameters of wheel loader operators. It combines case-based reasoning (CBR) with multivariate multiscale entropy analysis (MMSE) to fuse data from multiple physiological sensors. The MMSE algorithm is used to extract features from signals measured by sensors like ECG, finger temperature, skin conductance, and respiration rate. These features are used to form cases in a case library. The CBR approach then classifies new cases by retrieving similar past cases. The approach was evaluated on data from 18 professional drivers and achieved 83.33% accuracy in classifying subjects as "stressed" or "healthy", comparable to an expert's
Mental State Monitoring System for the Professional Drivers Based on Heart Ra...Reno Filla
The consequences of tiredness, drowsiness, stress and lack of concentration caused by a variety of different factors such as illness, sleep depletion, drugs and alcohol is a serious problem in traffic and when operating industrial equipment. This is especially important for professional drivers since both expensive equipment and lives may be at stake, e.g. in mining, construction and personal transportation, reduced concentration, stress or tiredness are known to be the cause of many accidents. A system which recognizes the state of the driver and e.g. suggests breaks when stress level is too high or driver is too tired would enable large savings and reduces accident. Today different sensors enable clinician to determine a driver’s status with high accuracy. The aim of the paper is to develop an intelligent system that can monitor drivers’ stress depending on psychological and behavioral conditions/status using heart rate variability. An experienced clinician is able to diagnose a person’s stress level based on sensor readings. Here, we propose a solution using case-based reasoning to diagnose individual driver’s stress. During calibration a number of individual parameters are established. The system also considers the feedback from the driver’s on how well the test was performed The validation of the approach is based on close collaboration with experts and measurements from 18 driver’s from Volvo Construction Equipment are used as reference.
http://www.mrtc.mdh.se/index.php?choice=publications&id=3046
Representative Testing of Emissions and Fuel Consumption of Working Machines ...Reno Filla
Out of necessity, emission and fuel consumption test cycles are a simplified representation of the real-life use of a vehicle or component that is assumed to be most common. In reality, variations are introduced by both the driver and the environment – and to a lesser degree also by the vehicle itself through performance deviations because of tolerances in the components’ characteristics. However, since such simplified test cycles exist and are accepted (or even required by law), OEMs tend to use them also in product development to benchmark their products against the competition, and to make decisions on how to optimize design.
While this approach might give acceptable results for on-road vehicles, it fails to capture reality in the case of versatile working machines. Here, the variety of possible applications cannot be covered by one common application but rather demands a mix of several cycles. This has a large impact on the setup and evaluation of physical and virtual testing of working machines, especially those with alternative power systems like hybrids, which will be discussed in the paper.
Attempts to simplify the complexity of real-life applications are made in some testing standards and standard proposals, but they over-simplify with the result of prescribing a common cycle that is not representative and which therefore, however tempting, cannot be used for any meaningful benchmarking of emissions and fuel consumption.
http://papers.sae.org/2012-01-1946
On Increasing Fuel Efficiency by Operator Assistance Systems in a Wheel LoaderReno Filla
This document discusses the potential for increasing fuel efficiency and productivity in wheel loaders through an operator assistant system. An empirical study found large variations between operators, with some achieving fuel efficiencies up to 200% higher and productivities up to 700% higher than others. The document argues that an operator assistant system could help all operators achieve the levels of the most efficient operators. It suggests a system that recommends optimal operations to the operator, with some automated functions, as a good starting point. Fuel efficiency improvements of 20-40% and productivity increases of 40-80% are estimated to be possible.
Programming Foundation Models with DSPy - Meetup SlidesZilliz
Prompting language models is hard, while programming language models is easy. In this talk, I will discuss the state-of-the-art framework DSPy for programming foundation models with its powerful optimizers and runtime constraint system.
Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
An English 🇬🇧 translation of a presentation to the speech I gave about the main changes brought by CCS TSI 2023 at the biggest Czech conference on Communications and signalling systems on Railways, which was held in Clarion Hotel Olomouc from 7th to 9th November 2023 (konferenceszt.cz). Attended by around 500 participants and 200 on-line followers.
The original Czech 🇨🇿 version of the presentation can be found here: https://www.slideshare.net/slideshow/hlavni-novinky-souvisejici-s-ccs-tsi-2023-2023-1695/269688092 .
The videorecording (in Czech) from the presentation is available here: https://youtu.be/WzjJWm4IyPk?si=SImb06tuXGb30BEH .
Freshworks Rethinks NoSQL for Rapid Scaling & Cost-EfficiencyScyllaDB
Freshworks creates AI-boosted business software that helps employees work more efficiently and effectively. Managing data across multiple RDBMS and NoSQL databases was already a challenge at their current scale. To prepare for 10X growth, they knew it was time to rethink their database strategy. Learn how they architected a solution that would simplify scaling while keeping costs under control.
TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
5th LF Energy Power Grid Model Meet-up SlidesDanBrown980551
5th Power Grid Model Meet-up
It is with great pleasure that we extend to you an invitation to the 5th Power Grid Model Meet-up, scheduled for 6th June 2024. This event will adopt a hybrid format, allowing participants to join us either through an online Mircosoft Teams session or in person at TU/e located at Den Dolech 2, Eindhoven, Netherlands. The meet-up will be hosted by Eindhoven University of Technology (TU/e), a research university specializing in engineering science & technology.
Power Grid Model
The global energy transition is placing new and unprecedented demands on Distribution System Operators (DSOs). Alongside upgrades to grid capacity, processes such as digitization, capacity optimization, and congestion management are becoming vital for delivering reliable services.
Power Grid Model is an open source project from Linux Foundation Energy and provides a calculation engine that is increasingly essential for DSOs. It offers a standards-based foundation enabling real-time power systems analysis, simulations of electrical power grids, and sophisticated what-if analysis. In addition, it enables in-depth studies and analysis of the electrical power grid’s behavior and performance. This comprehensive model incorporates essential factors such as power generation capacity, electrical losses, voltage levels, power flows, and system stability.
Power Grid Model is currently being applied in a wide variety of use cases, including grid planning, expansion, reliability, and congestion studies. It can also help in analyzing the impact of renewable energy integration, assessing the effects of disturbances or faults, and developing strategies for grid control and optimization.
What to expect
For the upcoming meetup we are organizing, we have an exciting lineup of activities planned:
-Insightful presentations covering two practical applications of the Power Grid Model.
-An update on the latest advancements in Power Grid -Model technology during the first and second quarters of 2024.
-An interactive brainstorming session to discuss and propose new feature requests.
-An opportunity to connect with fellow Power Grid Model enthusiasts and users.
Introduction of Cybersecurity with OSS at Code Europe 2024Hiroshi SHIBATA
I develop the Ruby programming language, RubyGems, and Bundler, which are package managers for Ruby. Today, I will introduce how to enhance the security of your application using open-source software (OSS) examples from Ruby and RubyGems.
The first topic is CVE (Common Vulnerabilities and Exposures). I have published CVEs many times. But what exactly is a CVE? I'll provide a basic understanding of CVEs and explain how to detect and handle vulnerabilities in OSS.
Next, let's discuss package managers. Package managers play a critical role in the OSS ecosystem. I'll explain how to manage library dependencies in your application.
I'll share insights into how the Ruby and RubyGems core team works to keep our ecosystem safe. By the end of this talk, you'll have a better understanding of how to safeguard your code.
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
Generating privacy-protected synthetic data using Secludy and MilvusZilliz
During this demo, the founders of Secludy will demonstrate how their system utilizes Milvus to store and manipulate embeddings for generating privacy-protected synthetic data. Their approach not only maintains the confidentiality of the original data but also enhances the utility and scalability of LLMs under privacy constraints. Attendees, including machine learning engineers, data scientists, and data managers, will witness first-hand how Secludy's integration with Milvus empowers organizations to harness the power of LLMs securely and efficiently.
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
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- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
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Monitoring and Managing Anomaly Detection on OpenShift.pdfTosin Akinosho
Monitoring and Managing Anomaly Detection on OpenShift
Overview
Dive into the world of anomaly detection on edge devices with our comprehensive hands-on tutorial. This SlideShare presentation will guide you through the entire process, from data collection and model training to edge deployment and real-time monitoring. Perfect for those looking to implement robust anomaly detection systems on resource-constrained IoT/edge devices.
Key Topics Covered
1. Introduction to Anomaly Detection
- Understand the fundamentals of anomaly detection and its importance in identifying unusual behavior or failures in systems.
2. Understanding Edge (IoT)
- Learn about edge computing and IoT, and how they enable real-time data processing and decision-making at the source.
3. What is ArgoCD?
- Discover ArgoCD, a declarative, GitOps continuous delivery tool for Kubernetes, and its role in deploying applications on edge devices.
4. Deployment Using ArgoCD for Edge Devices
- Step-by-step guide on deploying anomaly detection models on edge devices using ArgoCD.
5. Introduction to Apache Kafka and S3
- Explore Apache Kafka for real-time data streaming and Amazon S3 for scalable storage solutions.
6. Viewing Kafka Messages in the Data Lake
- Learn how to view and analyze Kafka messages stored in a data lake for better insights.
7. What is Prometheus?
- Get to know Prometheus, an open-source monitoring and alerting toolkit, and its application in monitoring edge devices.
8. Monitoring Application Metrics with Prometheus
- Detailed instructions on setting up Prometheus to monitor the performance and health of your anomaly detection system.
9. What is Camel K?
- Introduction to Camel K, a lightweight integration framework built on Apache Camel, designed for Kubernetes.
10. Configuring Camel K Integrations for Data Pipelines
- Learn how to configure Camel K for seamless data pipeline integrations in your anomaly detection workflow.
11. What is a Jupyter Notebook?
- Overview of Jupyter Notebooks, an open-source web application for creating and sharing documents with live code, equations, visualizations, and narrative text.
12. Jupyter Notebooks with Code Examples
- Hands-on examples and code snippets in Jupyter Notebooks to help you implement and test anomaly detection models.
Skybuffer SAM4U tool for SAP license adoptionTatiana Kojar
Manage and optimize your license adoption and consumption with SAM4U, an SAP free customer software asset management tool.
SAM4U, an SAP complimentary software asset management tool for customers, delivers a detailed and well-structured overview of license inventory and usage with a user-friendly interface. We offer a hosted, cost-effective, and performance-optimized SAM4U setup in the Skybuffer Cloud environment. You retain ownership of the system and data, while we manage the ABAP 7.58 infrastructure, ensuring fixed Total Cost of Ownership (TCO) and exceptional services through the SAP Fiori interface.
Ivanti’s Patch Tuesday breakdown goes beyond patching your applications and brings you the intelligence and guidance needed to prioritize where to focus your attention first. Catch early analysis on our Ivanti blog, then join industry expert Chris Goettl for the Patch Tuesday Webinar Event. There we’ll do a deep dive into each of the bulletins and give guidance on the risks associated with the newly-identified vulnerabilities.
Optimizing the trajectory of a wheel loader working in short loading cycles
1. The 13th Scandinavian International Conference on Fluid Power, SICFP2013, June 3-5, 2013, Linköping, Sweden
Optimizing the trajectory of a wheel loader working in short loading cycles
R. Filla
Emerging Technologies, Volvo Construction Equipment, Eskilstuna, Sweden
E-mail: reno.filla@volvo.com
Abstract
A study into alternative trajectories for wheel loaders working in short loading cycles has been
conducted, examining other patterns than the traditional V- or Y-cycle. Depending on
workplace setup and target function of the optimisation other trajectories can indeed prove
beneficial. The results of this study can be used in operator models for offline simulations as
well as for operator assistance or even in controllers for autonomous machines or energy
management systems for non-conventional machines like hybrids.
Keywords: wheel loader, working cycle, trajectory, work pattern, simulation, operator model,
control, operator assistance
1 Introduction
Figure 1, published in its first version in [1] and quoted in
several publications, shows the classic short loading cycle
with the characteristic driving pattern in the shape of a V,
possible to extend to a Y, if necessary.
Figure 1: Short loading cycle in classic V- or Y-pattern.
From phase 1 to 6, the wheel loader operator first fills the
bucket in the gravel pile, then drives backwards towards the
reversing point (phase 4) and steers the wheel loader to
accomplish the aforementioned characteristic V-pattern. The
lifting function is engaged the whole time. The operator
chooses the reversing point such that having arrived at the
load receiver and starting to empty the bucket (phase 6), the
lifting height will be sufficient to do so without delay. In
case of a bad matching between the machine’s travelling
speed and the lifting speed of the bucket, the operator needs
to drive back the wheel loader even further than necessary
for manoeuvring alone. This additional leg transforms the
V-pattern into a Y-pattern.
In the remaining phases 7 to 10, the bucket needs to be
lowered and the operator steers the wheel loader back to the
initial position in order to fill the bucket again in the next
cycle.
While the different phases of the depicted loading cycle are
generally applicable (even though in other circumstances it
might be meaningful to introduce new phases and events or
combine some of the phases shown in Figure 1), the driving
pattern does not necessarily have to resemble a V or Y. It
appears that this pattern has emerged from the operators’
desire to minimise the personal workload, rather than
maximise energy efficiency, for a required productivity.
For new non-conventional systems like (semi)autonomous
machines or hybrids, where the operator’s requirements are
less dominant or taken out of the loop completely, the
traditional cycle in Figure 1 is not necessarily the most
productive or the most energy-efficient way, either.
Improved energy management for such machines may
involve some kind of optimal control scheme along a pre-
defined trajectory – so the obvious question would be
whether there is optimisation potential in the trajectory
itself.
Even if accepting the V/Y-cycle as the trajectory to use, it is
an interesting question how to best orient the load receiver
for a given position. The traditional recommendations are a
90° or 135° angle, given not only by Volvo but also other
players in the industry [2][3]. However, also these recom-
mendations are based on the performance of conventional
2. systems and might not be valid for autonomous machines or
hybrids.
There is therefore a need to examine this in more detail and
the results can have various applications, from improved
dynamic simulations by adding planning capabilities to
operator models [4] over off-line use for education or site
planning purposes [5][6], on-line operator assistance
functions [7] to autonomous machines [8] and improved
energy management in advanced systems [9][10][11][12].
2 Problems of the classic V-/Y-cycle
A first attempt at examining different driving patterns has
been made by the author in [4] – however the work then
focused on a specific variant of the classic V-cycle without
further consideration of alternatives. When using this
trajectory in various workplace setups it becomes apparent
that its use is limited to tight places with loading and
unloading spot in close vicinity. For larger distances and
other orientations of the load receiver, the classic V-cycle
with equal steering to both sides very quickly results in
unreasonable long transporting distances (Figure 2 left and
right).
Figure 2: Classic V-cycle for different locations of the load
receiver (left) and different orientations (right).
This stems from the cycle being modelled as simply two
circular arcs meeting tangential in the reversal point. For
larger workplaces an experienced operator would gradually
vary the curve radius or at the very least extend the classic
trajectory with line segments rather than travel such long
distances in a curve with a very large radius.
Furthermore, above a certain transport distance any operator
will start using the wheel loader in a Load & Carry cycle
instead (Figure 3). In the “grey” area between tight working
places and wide ones other shapes of loading cycle
trajectories can serve as a smooth transition. Several
possible candidates have been examined in this study;
equations have been derived for easy implementation both
on-line and off-line.
Figure 3: Load & Carry cycle.
3 Overview of examined cycle variants
Expanding upon the variants briefly touched upon in [4]
Figure 4 shows the main cycle types and their respective
sub-variants that have been examined in this study.
Figure 4: Main cycle types and sub-variants examined in
this study. (Depicted load receiver position and orientation
is just an example.)
10− 0 10 20
60−
40−
20−
0
10− 0 10 20
60−
40−
20−
0
generic (g) compact (c)
(min #sections)
extreme (x)
(min turn radius)
A
B
C
D
E
F
G
Sub-variant
Maintype
H
I
(classic)
(same as Cc)
(same as Cc)
3. The first five main types “A” to “E” constitute a systematic
exploration of the classic V-/Y-cycle (which is labelled
“C”), while “F” and “G” represent a more intricate type with
one S-shaped leg and the other one straight. Finally, “H”
and “I” are permutations of the “C”-type with reversed order
of line and arc section in the second leg (“H”-type), and first
leg (“I”-type), respectively.
All cycles types studied can actually be seen as special cases
of one unified cycle type with the following properties:
• S-shaped legs with a linear section in between the
arc segments
• Length of linear segments can vary in interval
(-∞, ∞)
• Radius of arc segments can vary in interval
{[-∞, -Rmin_turn) , [Rmin_turn, ∞]}
• Section angle of arc segments can vary in interval
[0, 360°)
However, this unified cycle would have seven degrees of
freedom and an extremely large search space, due to the
parameter intervals also covering negative values. With the
current approach and the current tools at hand this seems
infeasible to solve in a reasonable amount of time.
Apart from the generic variant (sub-labelled “g”) with the
highest amount of degrees of freedom, each cycle type can
also be realised either as a compact cycle (sub-labelled “c”)
with as few segments per leg as possible or as an extreme
variant (“x”) where all curves are executed with highest
articulation angle and therefore smallest possible turning
radius.
4 Analysis
Table 1 shows the amount of degrees of freedom for each
cycle variant. While for example “Bc”, the compact variant
of the “B”-type, is fully constrained by the three parameters
of the workplace setup: orientation of the load receiver and
its vertical and horizontal distance from the loading spot, the
“Cg” variant has three degrees of freedom left to constrain,
which means that a parameter optimisation needs to be
performed, for example varying the angle of reversing and
the turning radii of both legs.
The equations for all cycle variants have been derived
analytically in order to achieve fast calculation. They have
been implemented in a collection of MathCad worksheets
and verified with parametric profiles in SolidEdge.
The high amount of degrees of freedom for certain cycle
variants and thus the necessity of parameter optimisation has
an impact on calculation times, however. Even though each
individual cycle variant can be calculated fairly quickly,
finding the optimal cycle with an optimal load receiver
orientation (i.e. an additional degree of freedom) for a given
load receiver position takes some seconds nonetheless.
Performing a massive workplace sweep as in Figure 15 and
Figure 16 takes several days on an average PC.
Table 1: Degrees of freedom for each cycle variant.
All cycle variants can be calculated in “strict” and “non-
strict” mode. In the former, the wheel loader is forced to
always arrive perpendicular to the load receiver, i.e. in a 90°
angle. An example from the field for such a scenario is an
immobile crusher with a ramp: neither can the crusher be
moved or rotated, nor can the wheel loader enter the ramp
other than reasonably aligned.
In contrast to this a conveyor belt, a pit or a submerged truck
are all fixed in position and orientation, but the wheel loader
serving them has some freedom in the approach for un-
loading. In “non-strict” calculations a permitted interval for
the angle of arrival is introduced, which adds an additional
degree of freedom and therefore increases calculation time
even more.
4.1 Delimitations
We only consider the part of the cycle between bucket
filling and bucket emptying, i.e. phases 2-5 according to
Figure 1.
The intended use of the results of this study for, among
others, on-line operator assistance functions, autonomous
machines, and improved energy management in advanced
systems excludes the possibility to perform detailed
dynamic simulations due to a limited time budget. The focus
has therefore been on calculations by means of explicit
equations for the trajectory parameters and properties.
However, this has the consequence that the effects of the
intricate dynamical interaction of engine, drive train and
hydraulics cannot be studied. One result is that all curve
trajectories are simplified as circular arcs. While circular
arcs merging tangential into each other seems smooth to the
outside observer, for the wheel loader it is not a smooth
manoeuvre at all. Any sudden change of curve radius
requires an equally sudden change of articulation angle.
With the masses of front and rear frame of a wheel loader,
this not only requires a certain amount of energy, but also
produces violent jerking. The use of arcs with a constant
radius is therefore only correct for a constant articulation
angle (Figure 5).
Sub-variant
g c x
A 2 1 0
B 1 0 0
C 3 1 1
D 1 0 0
E 2 1 0
F 3 2 1
G 3 2 1
H 3 (1) 1
I 3 (1) 1
Maintypes
4. Figure 5: Wheel loader in a turn, fixed articulation.
Any path transition needs to employ smooth changes of
radii. In most situations the wheel loader will be in
longitudinal motion while the steering function is used to
slowly change the frame articulation from a start value to a
value that results in the required turning radius (Figure 6)
Figure 6: Wheel loader in a turn, several stages from
straight to full turn.
This means that instead of following an arc with a constant
radius the wheel loader’s track will rather resemble a
clothoid or Euler spiral (provided that the change in
articulation angle is linear). Figure 7 shows in top view how
the curvature of a wheel loader’s trajectory is affected by
different machine speeds: in all traces (simulating a L120G
wheel loader model for 20s) the steering angle is increased
with a steering speed of 20% of maximum possible,
beginning with a straight machine (0° articulation) and a
cut-off at the machine’s maximum articulation angle. The
dashed line represents the theoretical turning circle, which
assumes an already established articulation angle of
maximum value. It can be seen that the higher the machine
speed, the higher the deviation of the actual trajectory from
the theoretical turning circle.
Figure 7: Wheel loader trajectories for different machine
speeds at constant steering speed (linearly increasing
articulation from 0° with cut-off at maximum).
Figure 8 shows how the curvature of a trajectory is affected
by different steering speeds (again simulating a L120G
wheel loader model for 20s). Not surprisingly, the lower the
steering speed, the higher the deviation of the actual
trajectory from the theoretical turning circle.
Figure 8: Wheel loader trajectories for different steering
speeds (linearly increasing articulation from 0° with cut-off
at maximum) at constant machine speed.
Modelling the curve trajectories as clothoids would require a
detailed simulation model that provides correct values for
machine speed and steering angle over time, which in turn
requires detailed modelling of the complete machine system
including actuation by the operator, engine dynamics, and
how hydraulics and drive train compete for the limited
engine power available.
As mentioned before, several of the intended applications of
the results of this study do not allow any detailed simulation
to be used anyway. In the case of optimal control we also
have arrived at a Catch-22 situation, where we would need a
detailed simulation in order to optimally control for example
energy management of a hybrid machine – in a simulation.
0 10 20
0
10
20
2.5 km/h, steeringspd 20%
5 km/h, steeringspd 20%
10 km/h, steeringspd 20%
theor. turning circle
0 10 20
0
10
20
5 km/h, steeringspd 100%
5 km/h, steeringspd 20%
5 km/h, steeringspd 10%
theor. turning circle
5. For this study we have therefore chosen to simplify and
approximate curves as circular arcs nonetheless. This
enables an analytical solution to all cycle variants to be
examined, which has a beneficial effect on the calculation
time that is required for optimisation.
This simplification leads to quite a significant deviation of
the actual machine position from the theoretical turning
radius when an established and maintained machine speed
of typically 10km/h is considered (Figure 9).
Figure 9: Error in position calculation due to simplification
(circular arcs instead of clothoids)
However, if we assume that for the most part a steering
action coincides with an acceleration of the machine from
stand-still (probably never attaining the typical speed of
10km/h), then the error caused by the simplification of
clothoid segments to circular arcs is tolerable, especially for
target steering angles of 20° and below (Figure 10).
Figure 10: Error in position calculation due to
simplification (circular arcs instead of clothoids)
4.2 Boundary conditions
The equations for cycle variant are set up so that the wheel
loader trajectory always joins perpendicular to the loading
spot and load receiver. The non-strict calculation mode, in
which the machine’s angle of arrival at the load receiver is
allowed within a pre-specified interval, is realised by
varying the load receiver orientation within the same
interval and perform strict calculations.
The arc segments have to be executed with a radius at least
equal to the specified wheel loader model’s minimum
turning radius.
Line segments that are enclosed by arcs and connect to the
reversing point are allowed to have negative length, so that
they can be executed either before or after reversing. This
applies to variants of cycle types “A”, “E”, “H” and “I”.
Additional boundary conditions ensure that prohibited
territory is not violated. For example, the trajectory is only
allowed to approach both load receiver and loading spot
from the front. It may also not go behind either one. The left
image in Figure 11 shows all such invalid trajectories (in
grey) for cycle variant “Cg” in a specific workplace setup.
The red trajectory is the optimal one.
Figure 11: Examples of valid and invalid trajectories
A safety perimeter (dotted circle in Figure 11) is established
around the load receiver, ensuring that trajectories do not
collide with the dump truck or crusher placed there. The
right image in Figure 11 shows all such invalid trajectories
(in grey) for cycle variant “Ec” in a specific workplace
setup. In the calculations performed in this study the safety
radius has been set to 3 meters.
4.3 Optimisation of cycle parameters
The degrees of freedom shown in Table 1 for each cycle
variant mean that the cycle trajectory is not fully constrained
just by knowing the load receiver position and orientation
(as discussed previously, these can become additional
degrees of freedom). Instead, some cycle parameters need to
be set explicitly – not by chance with a random value but
through optimisation with a value that maximises or
minimises a chosen property of the cycle.
Since most (if not all) optimisation problem in this study are
ill-conditioned and also non-smooth due to the boundary
conditions, after initial trial runs with different optimisation
algorithms it was decided to implement brute force opti-
misation instead. In most cases the optimisation parameter
was an angle that was to be varied in an interval of 180° or
less. Sweeping this interval in steps of one degree was easy
to do and improved performance noticeably. It was reasoned
that this would be precise enough because a human operator
is hardly able to perform a turn with even this precision.
But which target function to use for optimisation, i.e. what
distinguishes a better cycle in comparison to another
variant? The properties listed below are good candidates:
4− 2− 0 2 4
0
2
4
6
Position error in (x, y)
Δx (m)
Δ
y(m)
0 5 10 15 20
0
2
4
6
steer to 10°
steer to 20°
steer to 30°
steer to 40°
Total position error over time
time (s)
Δ
(m)
4− 2− 0 2 4
0
2
4
6
Position error in (x, y)
Δx (m)
Δ
y(m)
0 5 10 15 20
0
2
4
6
steer to 10°
steer to 20°
steer to 30°
steer to 40°
Total position error over time
time (s)
Δ
(m)
6. 1. driving distance
2. driving time
3. driving time including time for steering
4. productivity
5. energy efficiency
6. operator workload
We will discuss these proposals in the following sections.
4.4 Optimisation for driving distance
This is the most simple target function as it involves only
the calculation of the length of each individual segment,
which has to be done anyway.
It can be argued that optimising for “driving distance” also
covers the fuel consumption caused by energy requirements
of the drive train – at least to a certain extent, though not in
any greater detail.
4.5 Optimisation for driving time
The case can be made that not the driving distance matters,
but the time it takes to travel that distance. Calculating with
constant machine speed would just be the same as
optimising for driving distance, but the picture changes
when both the acceleration and the retardation of the
machine, together with a pre-defined maximum travelling
speed (Figure 12) are taken into account.
Figure 12: Speed profile over a cycle segment on which the
maximum travelling speed is reached.
Figure 13: Speed profile over a cycle segment on which the
maximum travelling speed is not reached.
When choosing the driving time as the target function for
optimisation, it might be an advantage to have one cycle
segment longer than the other, on which the machine can be
accelerated to maximum driving speed, giving a higher
mean speed for the complete cycle, rather than dividing the
cycle equally into two segments which are both too short to
result in maximum travelling speed until it is time again for
retardation (Figure 13).
Measurements from previous machine testing have been
used to determine typical acceleration and retardation rates;
and the maximum travelling speed is set such that no shift
into 3rd
gear is performed. With a simplified modelling like
this there is no need for detailed dynamic simulation, thus
calculation time is low as only linear equations are involved.
4.6 Optimisation for driving time including steering
Taking the travelling time due to longitudinal motion into
account is a first step but the influence of steering must also
be considered. In Figure 14 both trajectories have segments
of the same length, yet the turning radii of the curves in
trajectory 2 are smaller, which requires larger articulation.
In the point of reversing the operator needs to change
articulation from right to left, which takes more time for
tighter turns as in the second trajectory.
Figure 14: Cycle segments of the same length but different
turning radii, thus different steering angles.
We assume that the machine is not moving when steering. In
reality this would be the case, but then the curvature would
resemble clothoids and the driving distance would increase,
somewhat compensating for our simplified assumption.
Also, see Figure 10 which shows that the impact of this
simplification is minor for realistic machine acceleration and
steering speed values, especially for target articulation
angles of 20° and below.
4.7 Optimisation for productivity
Any meaningful optimisation for productivity must include
the bucket filling phase, because of the trade-off an operator
can make between the lifting height achieved when leaving
the loading spot (e.g. a pile of gravel) and the driving
distance required to achieve a lifting height sufficient for
emptying the bucket onto the load receiver.
vmax_theor
vmax = vmax_cycle < vmax_theor
time
speed
tacc tconst tbrake
vmax_cycle
Lacc Lconst Lbr
vmax = vmax_theor < vmax_cycle
time
speed
tacc tbrake
vmax_cycle
Lacc Lbr
Trajectory 1
Trajectory 2
timearticulationangle
time
articulationangle
∆t
7. This means we need to model different bucket filling
techniques, which requires a simulation with models of the
drivetrain and hydraulics of the machine, as well as models
of the operator and the material to be loaded. However, one
of the prerequisites for this study was to avoid detailed
simulations and employ analytical equations instead, as
discussed previously.
4.8 Optimisation for energy efficiency
Basically the same arguments put forth in the previous
section are also valid against choosing energy efficiency as
optimisation target, however with an even higher emphasis
on the model quality since power consumption is in the
focus, rather than time required for certain motions. The
most problematic requirement is the need for a high-quality
(and in terms of computation expense tolerable) model of
the material to be loaded. Today, great simplifications
would be needed in order to perform these simulations in a
reasonable time, which would be abused by the optimisation
algorithm to find the most energy-efficient way to fill the
bucket according to the (probably over-) simplified model –
not according to reality.
The option of only considering power consumption of the
drivetrain is not a valid work-around for a complex machine
such as a wheel loader [10]. Also, optimising for “driving
distance” already covers the drivetrain aspect to a certain
extent, though not in any greater detail.
4.9 Optimisation for operator workload
Apart from the difficulty to assess and quantify operator
workload in a computer simulation there is the general
problem of defining operator workload over a cycle.
If we would reduce it to encompass only control effort, then
the optimum would be a cycle variant with the least amount
of control input from loading to unloading – which is
implicitly already covered by the “driving time including
steering” option (section 4.6).
Any closer examination of operator workload would again
require detailed simulation however with a greatly improved
operator model.
5 Results
For any given workplace setup, consisting of orientation of
the load receiver and its vertical and horizontal distance
from the loading spot, each cycle variant can be calculated
without any great computational effort. Implementation in
autonomous machines and as assistance functions in wheel
loaders controlled by a human operator is therefore feasible.
However, the more degrees of freedom, the longer the
calculation time will be. Optimisation of all identified cycle
variants in “non-strict” mode requires significantly more
time, which might necessitate the implementation of pre-
calculated lookup tables. Using the MathCad worksheets
developed during this study a complete workplace area can
be screened and the optimal load receiver orientation
together with the parameters describing the optimal cycle
trajectory for each element in a matrix of load receiver
positions can be calculated.
5.1 Complete workplace area
Figure 15 shows the results of such a workplace parameter
sweep for a L120G wheel loader, optimised for “driving
time including steering”. In this calculation the load receiver
orientation was not specified either and added therefore to
the number of degrees of freedom – leading to quite a long
calculation time (several days, as mentioned previously).
Figure 15: Optimal cycle variant depending on workplace
However, the colour plot of Figure 15 does not reveal the
full picture, since the flexibility in several cycle variants
enables them to closely resemble the shape of another cycle
type – often of much simpler ones (see also Figure 16).
It is therefore more meaningful to examine cycle shapes (i.e.
the driving directions for the operator) rather than the cycle
variants (which are defined by the sets of equations they are
calculated from). Figure 16 shows the principle cycle shapes
that emerge as “driving time including steering”-optimal
within the calculated workplace parameter interval.
Figure 16: Optimal cycle shapes and optimal load receiver
orientations depending on workplace setup
(optimised for “driving time including steering”)
8. Judging from Figure 16 it seems clear that in the lower right
half of the workplace it is better to drive in reverse for most
of the distance. This is confirmed by plotting the relative
performance of single cycle types such as in Figure 17. It
can be seen that cycle type “C” is optimal (or very close to)
in the entire upper left area of the workplace, but not so in
the lower right area where “E” is optimal (except on the
very right edge where “E” is restricted by the safety radius
around the load receiver, leaving the field open to “C”).
Figure 17: Relative performance of cycle type “C”
compared to optimum in each single location
(optimised for “driving time including steering”)
Figure 17 also reveals that even though cycles types “D”
and “G” were presented as optimal in the upper left area of
Figure 15, cycle type “C” is more or less equally good. This
is again due to the actual shape of cycle types “G” and “C”
being optimised to resemble “D” – a sign that the additional
degrees of freedom in these cycles are not always needed.
However, Figure 18 shows that the area where cycle type
“D” is the optimum is not as large as for “C”.
Figure 18: Relative performance of cycle type “D”
compared to optimum in each single location
(optimised for “driving time including steering”)
Using such plots it can be shown that cycle type “E” is far
from being optimal in the upper left area of the workplace,
as well as that cycle types “A” and “B” are inferior in
generally all situations, provided the orientation of the load
receiver is not fixed.
However, it is difficult to generalise, since the observations
made above are valid for a specific wheel loader model and
a specific situation (safety radius, variable load receiver
orientation, etc.). In another setup with perhaps a more
restrictive safety perimeter around the load receiver and a
fixed orientation of the latter it might very well be the case
that cycles type “A” is superior to all others.
5.2 Specific load receiver locations, strict
In order to not use overly academic examples we designed a
test case that followed the recommendations given in the
literature. Acting upon the advice in [2][3] and others that a
tight “C”-type cycle shall be driven with no more than 1.5
wheel revolutions per leg or better ¾ to 1¼ (as experienced
professionals do), the load receiver, angled at 135° as
recommended, was positioned 3m to the side at 2m distance
from the loading spot.
Due to the tight work place setup some cycle variants are
prevented from reaching a valid solution. Figure 19 shows
that no valid solutions could be found for cycle types “E”
and “F” when optimising for driving distance. The optimal
cycle in this setup is a “C”-type cycle optimised as variant
“Cx” (trajectory and bar in red colour in Figure 19).
Figure 19: Test case optimised for driving distance
The blue trajectory and bar in Figure 19 belongs to “CcSR”,
a special case of a “Cc” cycle with a boundary condition that
both arcs shall have the same radius. This gives the same
articulation angle right and left for the wheel loaders
operator to steer to – probably a workload-minimising way
an operator might want to choose. It is presumed that this
(or the rather similar “CcSA”) is close to the classic V/Y-
cycle as depicted in Figure 1, where both legs are clearly
noticeable arcs (whereas a common “Cc” variant has one
degree of freedom left and can be optimised into having the
radius of one leg as nearly infinite, thus approaching a
straight line).
Driving a cycle according to this classic case “CcSR” would
have increased driving distance by 70% compared to the
optimal solution (blue trajectory and blue bar in Figure 19).
In comparison to the optimum “Cx”, an optimised “Dg”
cycle would have increased driving distance by 20%.
Optimising for driving time instead of driving distance does
not result in a significantly different outcome. Those cycle
variants with degrees of freedom get optimised into
9. basically the same shape. However, it is interesting to note
that the advantage of the optimal variant of “Cx” decreases,
so that classic case “CcSR” now only features a 30% higher
value for the driving time as opposed to a 70% higher
driving distance. The difference is due to the wheel loader
using the longer legs to accelerate to higher machine speed,
which greatly improves the average cycle speed.
The picture changes more significantly when optimising for
driving time including steering. Now there is also a penalty
on turning radii which require a lot of steering. Figure 20
shows that this favours a “D”-type cycle (but not “Dc” or
“Dx”), presumably because this cycle only requires the
wheel loader operator to use the steering function one time
during reversing. However, the advantage over, for example
the classic case “CcSR” is even smaller than previously: the
latter only suffers from a 10% increase in driving time when
the effects of steering are included.
Figure 20: Test case optimised for driving time including
steering
It is interesting to examine how the result changes with
different machine parameter values. For example, in the
calculation to the results in Figure 21 the wheel loader’s
steering speed has been reduced to half of its original value.
This has a profound negative impact on the “x” variants in
which all turns are executed with minimum radius, i.e.
maximum machine articulation. Cycle “Cx” takes now twice
the time to drive compared to the optimised “Dg”. The latter
now requires 17.8s to drive, compared to only 11.6s with the
original machine.
Figure 21: Test case optimised for driving time including
steering, machine with halved steering speed
In Figure 22 the machine performance has been boosted by
100% so that the values for typical acceleration, retardation
and steering speed are doubled. This favours a “Cg”-variant
that almost resembles the shape of a “D”-type cycle, but not
quite (though the driving time including steering is stated as
8.7s in both cases, so the difference is marginal). It is
interesting to see that the relative performance of all cycles
now varies less than when calculating with the original
machine parameters (Figure 20).
Figure 22: Test case optimised for driving time including
steering, machine with doubled acceleration, retardation
and steering speed
5.3 Specific load receiver locations, non-strict
In “non-strict” mode the wheel loader is permitted to arrive
at the load receiver with an angular deviation from the exact
90° that the “strict” scenario stipulates.
In the calculations in this study the interval is set to ±15°.
Figure 23 shows that this helps cycle type “F” to find a valid
solution when optimising for driving distance. The angle
deviation utilised by “Fx” is 11°, meaning that the best value
of this cycle type is calculated for arrival at 101°. All other
cycle types were able to find valid solutions already in
“strict” mode and prefer therefore to arrive at 75° instead.
Figure 23: Test case optimised for driving distance,
non-strict
In general, Figure 23 shows that “Cx” is still optimal when
driving distance is considered – however the classic case
“CcSR” now only shows a 50% higher value. It seems that
“Cx” profits more from the “non-strict” mode than “Dg”,
because the relative performance of the latter is 30% higher
than “Cx”, while it was only 20% higher in “strict” mode
(for comparison: in “strict” mode the “Cx” cycle resulted in
10.9m driving distance, compared to 9.4m in “non-strict”).
When optimising for driving time including steering, we see
that “Dg” is marked as the optimum in Figure 24 (in red),
however “Dc”, “Cc” and “Cg” do perform equally well. The
conclusion is that in this setup the optimal cycle shape is
that of “Dc” and the other cycles resemble that shape in their
10. respective optimised form. The angle deviation utilised
is -15°, i.e. the approach angle to the load receiver was 75°.
Figure 24: Test case optimised for driving time including
steering, non-strict
In general, “non-strict” calculations will result in less
variation in the relative performance of the cycle variants,
since each variant competes with many more individuals
than in “strict” mode. In the case of “F”-type cycles for our
chosen workplace setup we have seen that “non-strict” is
required to find a valid solution at all.
5.4 Specific load receiver locations, free orientation
In another set of MathCad worksheets calculations can be
performed where the load receiver location is still fixed, but
its orientation is considered an additional degree of freedom,
also to be optimised. This is in principle a serial execution
of the previously described calculations, conducted for all
possible load receiver angles in the interval [0°, 180°]. The
previously discussed calculation of a complete workplace
area is nothing more than a massive application of this,
performed for a matrix of load receiver locations.
Also these calculations too can be performed in “strict” or
“non-strict” setting, but in order to save space this paper will
not feature any example.
6 Discussion
The operator model published in [4] can adapt the cycle
trajectory to the working place, but the simulated wheel
loader will always be made to follow a resembling of the
classic “CcSR” case. The example calculations presented in
this paper show that this special case is not really optimal in
any scenario. The operator model can thus benefit from at
least implementing the full “C”-type.
Another application could be optimisation of the layout of a
construction site and even education of operators in how to
cooperate. Since several cycle types of different shape can
turn out to lead to approximately similar results, there might
be an opportunity for a sort of traffic management by letting
different wheel loaders take different trajectories in order to
avoid congestions.
However, it is easy to get carried away by mathematical
models, forgetting the delimitations. In this case it is
important to remember that in a real wheel loader the
trajectories will be clothoids rather than circular arc, with a
curvature that is dependent on the machine speed and the
steering speed, which in turn are both dependent on the
engine speed, controlled by the operator.
Also the balance of speed of the hydraulic functions and
machine speed is important to consider. As discussed
earlier, the operator chooses the reversing point such that
upon arrival at the load receiver the lifting height will be
sufficient to do start emptying the bucket immediately. In
case of a bad matching between the machine’s travelling
speed and the lifting speed of the bucket, the operator needs
to drive back the wheel loader even further than necessary
for manoeuvring alone. It is thus not guaranteed that a
theoretically optimal cycle variant is actually usable,
because the calculations employ static values for important
machine parameters such as steering speed and acceleration
rate.
It has been discussed in the beginning of this paper that one
application could be to give the operator tips in case the
machine detects a driving pattern that is perceived to be
inefficient. By employing machine learning techniques the
limitations of the use of static values may be overcome, at
least for a specific machine in a specific application (and
perhaps a specific operator, too).
Some, in certain cases slightly better, cycle variants can be
hard for a human operator to execute, for example the “E”-
type cycle in Figure 16 which involves backing the machine
at full speed, passing the load receiver at minimum distance
(as prescribed by the safety perimeter, in our examples set to
3m radius). An autonomous machine, on the other hand
would have no difficulties at performing this, thus being
able to realise even the small improvement potentials that
might lie in an optimised cycle pattern.
The example calculations discussed in this report were made
for a conventional wheel loader, but there might be a
difference for unconventional machines like hydraulic or
electric hybrids or a wheel loader equipped with a CVT
transmission. In any case energy management in these
advanced systems can profit from a higher degree of
situation awareness: knowledge about the current working
cycle and optimisation possibilities.
7 Conclusions
A study into alternative trajectories for short loading cycles
of wheel loaders has been conducted, examining other
patterns than the traditional V- or Y-cycle. Depending on
workplace setup and target function of the optimisation
other trajectories can indeed prove beneficial.
The results of this study can be used in operator models for
offline simulations as well as for operator assistance or even
in controllers for autonomous machines or energy
management systems for non-conventional machines like
hybrids.
However, the limitations of the approach utilised should be
taken into consideration.
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