To reduce the vertical vibration of the vehicle, the vehicle model including the axle dynamic
vibration absorber is established, and the vertical vibration acceleration spectrum of the wheel, the steering
frame and the body is obtained by numerical simulation. The vibration reduction effect of the dynamic vibration
absorber is analyzed. The results show that the axle dynamic vibration absorber not only has a good vibration
reduction effect on the wheel, but also has an important effect on the vertical vibration of the bogie and the
vehicle body.
In this study, vibration suppression of vehicle-bridge interaction system has been studied in
terms of bridge dynamics. In vibration suppression, some configurations of tuned passive mass dampers have
been considered. Motion equations of vehicle and absorbers are coupled with the motion equation of the bridge
beam using first four mode of beam and Lagrange equations. Then the coupled equation of vehicle-bridgeabsorbers
(VBA) has been solved using the fourth order Raunge-Kutta algorithm. It is proved that the
configuration of the absorbers that are placed on the anti-nodes of first and second mode shapes of the bridge
beam is the most effective one of all others.
Optimal Control for Torpedo Motion based on Fuzzy-PSO Advantage TechnicalTELKOMNIKA JOURNAL
The torpedo is a nonlinear object which is very difficult to control. Via to manage the rudder angle yaw, the diving plane angle, and the fin shake reduction, the torpedo yaw horizontal, the depth vertical and roll damping of the system are controlled accurately and steadily. In this paper, the particle swarm optimization is used to correct the imprecision of architecture fuzzy parameters. The coverage width of membership function and the overlap degree influence of neighboring membership functions are considered in the method to adjust dynamically from the system errors. Thereby optimizing the control signal and enhancing the torpedo motion quality. The proposed method results in a better performance compared to the other control method such as adaptive fuzzy-neural that proved effective of the proposed controller.
Measuring Axle Weight of Moving Vehicle Based on Particle Swarm OptimizationIJRES Journal
The dynamic tire forces are the important factor influencing weigh-in-motion of vehicle. This paper presents a method to separate the dynamic tire forces contained in axle-weight signal. On the basis of analyzing the characteristic of axle-weight signal, the model of axle-weight signal and the objective function are constructed. After introducing the principle of particle swarm optimization (PSO), an improved PSO is employed to estimate the unknown parameters of the objective function. According to the obtained estimates of parameters, the dynamic tire forces contained in axle-weight signal are reconstructed. Subtract the reconstructed dynamic tire forces from the axle-weight signal, and get the estimate of axle weight of moving vehicle. Simulation and field experiments are conducted to demonstrate the performance of the proposed method.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
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.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
In this study, vibration suppression of vehicle-bridge interaction system has been studied in
terms of bridge dynamics. In vibration suppression, some configurations of tuned passive mass dampers have
been considered. Motion equations of vehicle and absorbers are coupled with the motion equation of the bridge
beam using first four mode of beam and Lagrange equations. Then the coupled equation of vehicle-bridgeabsorbers
(VBA) has been solved using the fourth order Raunge-Kutta algorithm. It is proved that the
configuration of the absorbers that are placed on the anti-nodes of first and second mode shapes of the bridge
beam is the most effective one of all others.
Optimal Control for Torpedo Motion based on Fuzzy-PSO Advantage TechnicalTELKOMNIKA JOURNAL
The torpedo is a nonlinear object which is very difficult to control. Via to manage the rudder angle yaw, the diving plane angle, and the fin shake reduction, the torpedo yaw horizontal, the depth vertical and roll damping of the system are controlled accurately and steadily. In this paper, the particle swarm optimization is used to correct the imprecision of architecture fuzzy parameters. The coverage width of membership function and the overlap degree influence of neighboring membership functions are considered in the method to adjust dynamically from the system errors. Thereby optimizing the control signal and enhancing the torpedo motion quality. The proposed method results in a better performance compared to the other control method such as adaptive fuzzy-neural that proved effective of the proposed controller.
Measuring Axle Weight of Moving Vehicle Based on Particle Swarm OptimizationIJRES Journal
The dynamic tire forces are the important factor influencing weigh-in-motion of vehicle. This paper presents a method to separate the dynamic tire forces contained in axle-weight signal. On the basis of analyzing the characteristic of axle-weight signal, the model of axle-weight signal and the objective function are constructed. After introducing the principle of particle swarm optimization (PSO), an improved PSO is employed to estimate the unknown parameters of the objective function. According to the obtained estimates of parameters, the dynamic tire forces contained in axle-weight signal are reconstructed. Subtract the reconstructed dynamic tire forces from the axle-weight signal, and get the estimate of axle weight of moving vehicle. Simulation and field experiments are conducted to demonstrate the performance of the proposed method.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
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.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Troubleshooting and Enhancement of Inverted Pendulum System Controlled by DSP...Thomas Templin
An inverted pendulum is a pendulum that has its center of mass above its pivot point. It is often implemented with the pivot point mounted on a cart that can move horizontally and may be called a cart-and-pole system. A normal pendulum is always stable since the pendulum hangs downward, whereas the inverted pendulum is inherently unstable and trivially underactuated (because the number of actuators is less than the degrees of freedom). For these reasons, the inverted pendulum has become one of the most important classical problems of control engineering. Since the 1950s, the inverted-pendulum benchmark, especially the cart version, has been used for the teaching and understanding of the use of linear-feedback control theory to stabilize an open-loop unstable system.
The objectives of this project are to:
• Focus on hardware and software troubleshooting and enhancement of an inverted-pendulum system controlled by a DSP28355 microprocessor and CCSv7.1 software.
• Use the swing-up strategy to move the pendulum into the unstable upward position (‘saddle’). The cart/pole system employs linear bearings for back-and-forward motion. The motor shaft has a pinion gear that rides on a track permitting the cart to move in a linear fashion. Both rack and pinion are made of hardened steel and mesh with a tight tolerance. The rack-and-pinion mechanism eliminates undesirable effects found in belt-driven and free-wheel systems, such as slippage or belt stretching, ensuring consistent and continuous traction.
• The motor shaft is coupled to a high-resolution optical encoder that accurately measures the position of the cart. The angle of the pendulum is also measured by an optical encoder, and the system employs an LQR controller to stabilize the pendulum rod at the unstable-equilibrium position.
• Addition of real-time status reporting and visualization of the system.
For the project, the Quanser High Frequency Linear Cart (HFLC) was used. The HFLC system consists of a precisely machined solid aluminum cart driven by a high-power 3-phase brushless DC motor. The cart slides along two high-precision, ground-hardened stainless steel guide rails, allowing for multiple turns and continuous measurement over the entire range of motion.
Our team implemented a control strategy that consists of a linear stabilizing LQR controller, proportional-integral swing-up control, and a supervisory coordinator that determines the control strategy (LQR or swing-up) to be used at any given time. The function of the linear stabilizer is to stabilize the system when it is in the vicinity of the unstable equilibrium. When the pendulum is in its natural state (straight-down stable-equilibrium node), the swing-up controller provides the cart/pendulum system with adequate energy to move the pendulum to the unstable equilibrium inside the “region of attraction” in which the linearized LQR controller is functional.
This presentation introduces the concept of "impact reduction factor" and a new method that are both developed by Dr. Niyazi Özgür Bezgin to estimate vertical impact forces on railways due to track stiffness variations.
Design and Fabrication of a Tricycle for Municipal Waste Collectioninventionjournals
ABSTRACT: The use of inappropriate technology for the primary collection of municipal wastes in general is a common problem. A tricycle was designed and fabricated with a carriage to be used for doorstep collection of waste. The tricycle was designed to be human powered for the purpose of primary collection of municipal solid waste in locations and communities where the existing collection trucks could not cover due to narrow, poor quality roads and a high density population and congested areas. The final result shows that the tricycle is stable, strong, durable, and the dynamic test conducted has confirmed the stability, easy maneuvering, and the effectiveness of the braking system. This research work is applicable to the reduction in the inefficiency with the existing methods and equipment used in the collection of municipal waste.
Mathematical Modeling and Simulation of Two Degree of Freedom Quarter Car Modelijsrd.com
The proposed study is to develop an active suspension system to increase the comfort for the passenger by reducing the body acceleration. The dynamic quarter car suspension system is considered for mathematical modelling and simulation is carried using MATLAB SIMULINK. The present suspension system is controlled by Proportional- Integral -Derivative controller. The system performance is analysed using the single speed bump road surface and the effectiveness is evaluated with active and passive controlled systems.
Tc 202-transportation geotechnics and geoecology conferenceOzgur Bezgin
This presentation presents the concept of "Impact Reduction Factor" and the "Bezgin Impact Factor" to estimate vertical impact forces on railways due to track profile variation.
Vibration Analysis of Cracked Rotor Using Numerical ApproachIOSR Journals
In general rotating machines have wide applications in systems, plants, vehicles, and industries. Every rotating machine uses shaft as power transforming unit. It is very dangerous to operate the machine with the presence of crack in the shaft. The growth of the crack is dangerous to operate and may lead to catastrophic failure. It is to be detected at earlier stages. In this paper relation between vibration amplitude and on the crack depth was developed, this helps in determine the depth of the crack by measuring the vibration amplitudes. To develop the relation equation strain energy density function was used. By observing the generated curves amplitude of vibration increases with respect to the depth of the crack due to reduction in stiffness of the shaft.
Troubleshooting and Enhancement of Inverted Pendulum System Controlled by DSP...Thomas Templin
An inverted pendulum is a pendulum that has its center of mass above its pivot point. It is often implemented with the pivot point mounted on a cart that can move horizontally and may be called a cart-and-pole system. A normal pendulum is always stable since the pendulum hangs downward, whereas the inverted pendulum is inherently unstable and trivially underactuated (because the number of actuators is less than the degrees of freedom). For these reasons, the inverted pendulum has become one of the most important classical problems of control engineering. Since the 1950s, the inverted-pendulum benchmark, especially the cart version, has been used for the teaching and understanding of the use of linear-feedback control theory to stabilize an open-loop unstable system.
The objectives of this project are to:
• Focus on hardware and software troubleshooting and enhancement of an inverted-pendulum system controlled by a DSP28355 microprocessor and CCSv7.1 software.
• Use the swing-up strategy to move the pendulum into the unstable upward position (‘saddle’). The cart/pole system employs linear bearings for back-and-forward motion. The motor shaft has a pinion gear that rides on a track permitting the cart to move in a linear fashion. Both rack and pinion are made of hardened steel and mesh with a tight tolerance. The rack-and-pinion mechanism eliminates undesirable effects found in belt-driven and free-wheel systems, such as slippage or belt stretching, ensuring consistent and continuous traction.
• The motor shaft is coupled to a high-resolution optical encoder that accurately measures the position of the cart. The angle of the pendulum is also measured by an optical encoder, and the system employs an LQR controller to stabilize the pendulum rod at the unstable-equilibrium position.
• Addition of real-time status reporting and visualization of the system.
For the project, the Quanser High Frequency Linear Cart (HFLC) was used. The HFLC system consists of a precisely machined solid aluminum cart driven by a high-power 3-phase brushless DC motor. The cart slides along two high-precision, ground-hardened stainless steel guide rails, allowing for multiple turns and continuous measurement over the entire range of motion.
Our team implemented a control strategy that consists of a linear stabilizing LQR controller, proportional-integral swing-up control, and a supervisory coordinator that determines the control strategy (LQR or swing-up) to be used at any given time. The function of the linear stabilizer is to stabilize the system when it is in the vicinity of the unstable equilibrium. When the pendulum is in its natural state (straight-down stable-equilibrium node), the swing-up controller provides the cart/pendulum system with adequate energy to move the pendulum to the unstable equilibrium inside the “region of attraction” in which the linearized LQR controller is functional.
This presentation introduces the concept of "impact reduction factor" and a new method that are both developed by Dr. Niyazi Özgür Bezgin to estimate vertical impact forces on railways due to track stiffness variations.
Design and Fabrication of a Tricycle for Municipal Waste Collectioninventionjournals
ABSTRACT: The use of inappropriate technology for the primary collection of municipal wastes in general is a common problem. A tricycle was designed and fabricated with a carriage to be used for doorstep collection of waste. The tricycle was designed to be human powered for the purpose of primary collection of municipal solid waste in locations and communities where the existing collection trucks could not cover due to narrow, poor quality roads and a high density population and congested areas. The final result shows that the tricycle is stable, strong, durable, and the dynamic test conducted has confirmed the stability, easy maneuvering, and the effectiveness of the braking system. This research work is applicable to the reduction in the inefficiency with the existing methods and equipment used in the collection of municipal waste.
Mathematical Modeling and Simulation of Two Degree of Freedom Quarter Car Modelijsrd.com
The proposed study is to develop an active suspension system to increase the comfort for the passenger by reducing the body acceleration. The dynamic quarter car suspension system is considered for mathematical modelling and simulation is carried using MATLAB SIMULINK. The present suspension system is controlled by Proportional- Integral -Derivative controller. The system performance is analysed using the single speed bump road surface and the effectiveness is evaluated with active and passive controlled systems.
Tc 202-transportation geotechnics and geoecology conferenceOzgur Bezgin
This presentation presents the concept of "Impact Reduction Factor" and the "Bezgin Impact Factor" to estimate vertical impact forces on railways due to track profile variation.
Vibration Analysis of Cracked Rotor Using Numerical ApproachIOSR Journals
In general rotating machines have wide applications in systems, plants, vehicles, and industries. Every rotating machine uses shaft as power transforming unit. It is very dangerous to operate the machine with the presence of crack in the shaft. The growth of the crack is dangerous to operate and may lead to catastrophic failure. It is to be detected at earlier stages. In this paper relation between vibration amplitude and on the crack depth was developed, this helps in determine the depth of the crack by measuring the vibration amplitudes. To develop the relation equation strain energy density function was used. By observing the generated curves amplitude of vibration increases with respect to the depth of the crack due to reduction in stiffness of the shaft.
INTEGRATED INERTER DESIGN AND APPLICATION TO OPTIMAL VEHICLE SUSPENSION SYSTEMijcax
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.
INTEGRATED INERTER DESIGN AND APPLICATION TO OPTIMAL VEHICLE SUSPENSION SYSTEMijcax
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.
COMPARISON OF RESPONSE TO UNBALANCE OF OVERHUNG ROTOR SYSTEM FOR DIFFERENT SU...IAEME Publication
Rotor unbalance is most common fault found in the rotating machines. Methods
are adopted to analyze the position of unbalance and to bring its effect into acceptablelimit. Vibration analysis is the most common technique used to analyze the rotor
system. Research have been performed on rotor supported atboth ends, however lessstudy has been done for overhung rotor. In this paper the response of overhung rotoron isotropic support and anisotropic support subject tounbalance has been presented.and equations aresolved using MATLAB programming. The effect of unbalancehas been studied on thebode plot. Forward and Reverse whirl are observed through Campbell diagram andmode shapes are plotted.
Stability analysis of a Rigid Vehicle Modelsaeid ghaffari
The lateral stability of a two axle vehicle with open loop control will be studied in this project. A 3 dof model is adopted to evaluate the curvature gain and the root loci as a function of the vehicle speed V. Moreover, the dynamic response of the vehicle considering the step steer manoeuvre will be analysed according to the ISO norm. The side slip angle and the yaw rate are evaluated as a function of time, while the trajectory of the center of gravity G of the vehicle with respect to the inertial reference frame (OXY Z) is plotted during step steer maneuver. Inasmuch as the change of cornering stiffness on tires due to the different condition are small, we cannot see the difference between the trajectories, shedding light on the steering angles, however, we can understand what is happening in various conditions. In this study, both the effect of traction force on the front and rear axle and transversal load transfer on the front and rear axle are investigated.
*only the first 10 pages of the main project are presented here. If you are interested to go through the rest of this document please contact me via saeid.ghaffari@studenti.polito.it.
Bifurcation Analysis of High-Speed Railway Vehicle in a CurveIDES Editor
In order to prevent unpleasant incidents,
preservation high-speed railway vehicle stability has vital
importance. For this purpose, railway vehicle is modeled using
a 38-DOF. This paper presents an investigation on limit cycle
and bifurcation of high speed railway behavior. It is revealed
that the critical hunting speed decreases by increasing the
wheel conicity. Also the critical hunting speed and hunting
frequency calculated via the linear elastic rail is higher than
that derived using a nonlinear model.
THE INFLUENCE OF DRIVING AXLE LOCATION ON THE LATERAL FORCE OF VEHICLEIAEME Publication
The lateral force acting on the tires produces a side slip angle that affects the
directional stability of vehicle. This paper presents some research results of the
influence of driving axle location on the lateral force of vehicle with 4x2 wheel
formula when vehicle is turning. The single track dynamical models of FWD and RWD
vehicle while cornering are created. Based on these two dynamical models, the system
equations of motion built are enable to study the influence of driving axle location on
the lateral force. Some calculated simulation results are shown for illustration.
Strength Analysis and Optimization Design about the key parts of the RobotIJRES Journal
Study on structure optimization design about Flip Arms of Mobile Robot. First conducted
preliminary structural design, and established finite element analysis model by HYPERMESH, use ANSYS
software to study Flip Arms Stress distribution and structure optimization. Strength check to ensure the strength
and stiffness of Flip Arms meet safety requirements, and make sure the reliability of the design, to provide a
theoretical basis for the structural optimization design of Flip Arms. Optimization design considering the
weighted compliance as the object function, the frame was improved by modifying the parameters which are
most sensitive to the character of the frame structure. The results showed that structural optimization design
without affecting the reliability of Flip Arms, reducing the quality of the parts improved and the Flip Arms
flexible mobility, to provide a theoretical basis for the structural design of robot.
Exploratory study on the use of crushed cockle shell as partial sand replacem...IJRES Journal
The increasing demand for natural river sand supply for the use in construction industry along
with the issue of environmental problem posed by the dumping of cockle shell, a by-product from cockle
business have initiated research towards producing a more environmental friendly concrete. This research
explores the potential use of cockle shell as partial sand replacement in concrete production. Cockle shell used
in this experimental work were crushed to smaller size almost similar to sand before mixed in concrete. A total
of six concrete mixtures were prepared with varying the percentages of cockle shell viz. 0%, 5%, 10%, 15%,
20% and 25%. All the specimens were subjected to continuous water curing. The compressive strength test was
conducted at 28 days in accordance to BS EN 12390. Finding shows that integration of suitable content of
crushed cockle shell of 10% as partial sand replacement able to enhance the compressive strength of concrete.
Adopting crushed cockle shell as partial sand replacement in concrete would reduce natural river sand
consumption as well as reducing the amount of cockle shell disposed as waste.
Congenital Malaria: Correlation of Umbilical Cord Plasmodium falciparum Paras...IJRES Journal
The vertical (trans-placental) transmission of the parasite Plasmodium falciparum from
pregnant mother to fetus during gestational period was investigated in a clinical research involving 43 full term
pregnant women in selected Hospitals in Jimeta Yola, Adamawa State Nigeria. During the observational study,
parasitemia was determined by light microscopic examination of umbilical and maternal peripheral blood film
for the presence of the trophozoites of Plasmodium falciparum. Correlational analysis was then carried on the
result obtained at p<0.05.><0.05) was established between maternal peripheral blood and umbilical cord
blood parasitemia with Pearson’s correlation coefficient of 0.762. Thus, in a malaria endemic area like Yola,
Adamawa State, Nigeria, with a stable transmission of parasite, there is a high probability of vertical
transmission of Plasmodium falciparum parasite from mother to fetus during gestation that can be followed by
the presentation of the symptoms of malaria by the newborn and other malaria related complications. Families
are advised to consistently sleep under appropriately treated insecticide mosquito net to avoid mosquito bite and
subsequent infestation.
Review: Nonlinear Techniques for Analysis of Heart Rate VariabilityIJRES Journal
Heart rate variability (HRV) is a measure of the balance between sympathetic mediators of heart
rate that is the effect of epinephrine and norepinephrine released from sympathetic nerve fibres acting on the
sino-atrial and atrio-ventricular nodes which increase the rate of cardiac contraction and facilitate conduction at
the atrio-ventricular node and parasympathetic mediators of heart rate that is the influence of acetylcholine
released by the parasympathetic nerve fibres acting on the sino-atrial and atrio-ventricular nodes leading to a
decrease in the heart rate and a slowing of conduction at the atrio-ventricular node. Sympathetic mediators
appear to exert their influence over longer time periods and are reflected in the low frequency power(LFP) of
the HRV spectrum (between 0.04Hz and 0.15 Hz).Vagal mediators exert their influence more quickly on the
heart and principally affect the high frequency power (HFP) of the HRV spectrum (between 0.15Hz and 0.4
Hz). Thus at any point in time the LFP:HFP ratio is a proxy for the sympatho- vagal balance. Thus HRV is a
valuable tool to investigate the sympathetic and parasympathetic function of the autonomic nervous system.
Study of HRV enhance our understanding of physiological phenomenon, the actions of medications and disease
mechanisms but large scale prospective studies are needed to determine the sensitivity, specificity and predictive
values of heart rate variability regarding death or morbidity in cardiac and non-cardiac patients. This paper
presents the linear and nonlinear to analysis the HRV.
Dynamic Modeling for Gas Phase Propylene Copolymerization in a Fluidized Bed ...IJRES Journal
A two-phase model is proposed for describing the dynamics of a fluidized bed reactor used for
polypropylene production. In the proposed model, the fluidized bed is divided into an emulsion and bubble
phase where the flow of gas is considered to be plug flow through the bubbles and perfectly mixed through the
emulsion phase. Similar previous models, consider the reaction in the emulsion phase only. In this work the
contribution of reaction in the bubble phase is considered and its effect on the overall polypropylene production
is investigated the kinetic model is combined with hydrodynamic model in order to develop a comprehensive
model for gas-phase propylene copolymerization reactor. Simulation profiles of the proposed model were
compared with those of well mixed model for the emulsion phase temperature. The simulated temperature
profile showed a lower rate of change compared to the previously reported models due to lower polymerization
rate. Model simulation showed that about 13% of the produced polymer comes from the bubble phase and this
considerable amount of polymerization in the bubbles should not be neglected in any modeling attempt.
Study and evaluation for different types of Sudanese crude oil propertiesIJRES Journal
Sudanese crude oil is regarded as one of the sweet types of crude in the world, Sulphur containing
compounds are un desirable in petroleum because they de activate the catalyst during the refining processes and
are the main source of acid rains and environmental pollution.(Mark Cullen 2001),Since it contains considerable
amount of salts and acids, it negatively impact the production facilities and transportation lines with corrosive
materials. However it suffers other problems in flow properties represented by the high viscosity and high
percentage of wax. Samples were collected after the initial and final treatment at CPF, and tested for
physical and chemical properties.wax content is in the range 23-31 weight % while asphalting content is about
0.1 weight% . Resin content is 13-7 weight % and deposits are 0.01 weight%. The carbon number distribution in
the crude is in the range 7-35 carbon atoms. The pour point vary between 39°C-42°C and the boiling point is in
the range 70 °C - 533 °C.
A Short Report on Different Wavelets and Their StructuresIJRES Journal
This article consists of basics of wavelet analysis required for understanding of and use of wavelet
theory. In this article we briefly discuss about HAAR wavelet transform their space and structures.
A Case Study on Academic Services Application Using Agile Methodology for Mob...IJRES Journal
Recently, Mobile Cloud Computing reveals many modern development areas in the Information
Technology industry. Several software engineering frameworks and methodologies have been developed to
provide solutions for deploying cloud computing resources on mobile application development. Agile
methodology is one of the most commonly used methodologies in the field. This paper presents the MCCAS a
Web and Mobile application that provide feature for the Palestinian higher education/academic institutions. An
Agile methodology was used in the development of the MCCAS but in parallel with emphasis on Cloud
computing resources deployment. Also many related issues is discussed such as how software engineering
modern methodologies (advances) influenced the development process.
Wear Analysis on Cylindrical Cam with Flexible RodIJRES Journal
Firstly, the kinetic equation of spatial cylindrical cam with flexible rod has been established. Then, an
accurate cylindrical cam mechanism model has been established based on the spatial modeling software
Solidworks. The dynamic effect of flexible rod on mechanical system was studied in detail based on the
mechanical system dynamics analytical software Adams, and Archard wear model is used to predict the wear of
the cam. We used Ansys to create finite element model of the cam link, extracted the first five order mode to
export into Adams. The simulation results show that the dynamic characteristics of spatial cylindrical cam
mechanical system with flexible rod is closed to ideal mechanism. During the cam rotate one cycle, the collision
in the linkage with a clearance occurs in some special location, others still keep a continuous contact, and the
prediction of wear loss is smaller than rigid body.
DDOS Attacks-A Stealthy Way of Implementation and DetectionIJRES Journal
Cloud Computing is a new paradigm provides various host service [paas, saas, Iaas over the internet.
According to a self-service,on-demand and pay as you use business model,the customers will obtain the cloud
resources and services.It is a virtual shared service.Cloud Computing has three basic abstraction layers System
layer(Virtual Machine abstraction of a server),Platform layer(A virtualized operating system, database and
webserver of a server and Application layer(It includes Web Applications).Denial of Service attack is an attempt
to make a machine or network resource unavailable to the intended user. In DOS a user or organization is
deprived of the services of a resource they would normally expect to have.A Successful DOS attack is a highly
noticeable event impacting the entire online user base.DOS attack is found by First Mathematical Metrical
Method (Rate Controlling,Timing Window,Worst Case and Pattern Matching)DOS attack not only affect the
Quality of the service and also affect the performance of the server. DDOS attacks are launched from Botnet-A
large Cluster of Connected device(cellphone,pc or router) infected with malware that allow remote control by an
attacker. Intruder using SIPDAS in DDOS to perform attack.SIPDAS attack strategies are detected using Heap
Space Monitoring Algorithm.
An improved fading Kalman filter in the application of BDS dynamic positioningIJRES Journal
Aiming at the poor dynamic performance and low navigation precision of traditional fading
Kalman filter in BDS dynamic positioning, an improved fading Kalman filter based on fading factor vector is
proposed. The fading factor is extended to a fading factor vector, and each element of the vector corresponds to
each state component. Based on the difference between the actual observed quantity and the predicted one, the
value of the vector is changed automatically. The memory length of different channel is changed in real time
according to the dynamic property of the corresponding state component. The actual observation data of BDS is
used to test the algorithm. The experimental results show that compared with the traditional fading Kalman filter
and the method of the third references, the positioning precision of the algorithm is improved by 46.3% and
23.6% respectively.
Positioning Error Analysis and Compensation of Differential Precision WorkbenchIJRES Journal
Positioning error is a widely problem exists in mechanism, the important factors affecting machining
precision. In order to reduce the error caused by positioning problem processing, based on the differential
workbench as the research object, using the method of theoretical analysis and experimental verification, the
analysis of positioning error mechanism and source of complete differential precision workbench error
compensation, improve the accuracy of the device, provides a method for the application of modern machine
tools. table.
Status of Heavy metal pollution in Mithi river: Then and NowIJRES Journal
The Mithi River runs through the heart of suburban Mumbai. Its path of flow has been severely
damaged due to industrialization and urbanization. The quality of water has been deteriorating ever since. The
Municipal and industrial effluents are discharged in unchecked amounts. The municipal discharge comprises
untreated domestic and sewage wastes whereas the industries are majorly discharge chemicals and other toxic
effluents which are responsible in increasing the metal load of the river. In the current study, the water is
analysed for heavy metals- Copper, Cadmium, Chromium, Lead and Nickel. It also includes a brief
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Study on Vibration Reduction Effect of the Rail Vehicle with Axle Dynamic Vibration Absorber
1. International Journal of Research in Engineering and Science (IJRES)
ISSN (Online): 2320-9364, ISSN (Print): 2320-9356
www.ijres.org Volume 3 Issue 11 ǁ November. 2015 ǁ PP.12-17
www.ijres.org 12 | Page
Study on Vibration Reduction Effect of the Rail Vehicle with Axle
Dynamic Vibration Absorber
LI Qiong, WEN Yong-peng*
, ZHOU Wei-hao, XU Xiao-jun
(College of Urban Railway Transportation, Shanghai University of Engineering Science, China)
ABSTRACT: To reduce the vertical vibration of the vehicle, the vehicle model including the axle dynamic
vibration absorber is established, and the vertical vibration acceleration spectrum of the wheel, the steering
frame and the body is obtained by numerical simulation. The vibration reduction effect of the dynamic vibration
absorber is analyzed. The results show that the axle dynamic vibration absorber not only has a good vibration
reduction effect on the wheel, but also has an important effect on the vertical vibration of the bogie and the
vehicle body.
Keywords: Dynamic vibration absorber, Axle, Vertical vibration, Mass ratio, Damping
I. INTRODUCTION
The vibration of rail vehicle may cause wheel, bogie and other components cracks and other damages,
which may affect the safe operation of the vehicle. V The wheel-rail interaction leads to vehicle vibration and
passes primary and second suspension system to the bogie and the car body. Therefore, the research on vehicle
vibration damping device is very necessary.
At present, many scholars have studied the vehicle model, Zhai Wan-ming[1] established a vehicle/track
coupled mode. The vehicle was simplified as a multi-degree of freedom model, the track is considered as
a Timoshenko beam, Vehicle and track model are considered more complete; Zhao Honglun [2] established a
finite element model of vehicle systems for analysis, and provided a reference for the development of rail
vehicles. In addition, in order to reduce the vertical vibration of the vehicle, many scholars have established a
vehicle model with dynamic vibration absorber, Foo [3] proposed a dynamic vibration absorber which is
installed at the bottom of the car body, The results show that vibration can be reduced in some parts of the
vehicle body; Zeng Jing [4] established the vehicle model installation dynamic vibration absorber and
analysis its damping, The research results show that the damping performance of the vibration absorbers is very
good in the low frequency and at speed greater than 150km/h; Zhou Jingsong [5-6]established the
vehicle model with dynamic vibration absorber, and introduced the vehicle running stability index to discuss the
damping performance of vehicle dynamic vibration absorber, obtain that dynamic vibration absorber can
make the running stability of vehicles reached excellent, and the higher its quality the better its damping
performance; Tomioka [7]considered the bogie as a dynamic vibration absorber. The research results show that
it can significantly reduce the bending vibration of car body. In general, the vehicle model is becoming more
and more complex, and the results are more realistic. Moreover, the dynamic vibration absorber is seemed as a
an effective device for vehicle vibration reduction.
Therefore, according to Lagrange equation, in order to reduce the vertical vibration of the vehicle, we
establish vehicle dynamics model with an axle dynamic vibration absorber, in which the dynamic vibration
absorber mounted on the axle portion of the system by reducing wheel vibration throughout the vehicle to
reduce the effect of vibration. According to the obtained vehicle acceleration power spectral density of the
components, vehicle dynamic vibration absorber damping effect is analysis carefully.
II. WHEEL MODEL
The dynamic vibration absorber is mounted on the axle, as shown in Fig. 1, the axle wrap a layer of shock-
absorbing materials and vibration absorber simplified model to simplify mass, spring and damping is shown in
Fig. 2. Model has a body of ups and downs and nod (two degrees of freedom), front and rear bogies of ups and
downs and nod (four degrees of freedom), four wheels drifting (four degrees of freedom) and dynamic vibration
absorber ups and downs (one degree of freedom) simplified model fourteen degrees of freedom.
*Corresponding author
E-mail address: yp_wen@163.com
2. Study on Vibration Reduction Effect of the Rail Vehicle with Axle Dynamic Vibration Absorber
www.ijres.org 13 | Page
Fig.1 Wheel of dynamic vibration absorber schematic
Fig.2 Vehicle model including the dynamic vibration absorber of a wheel
In Fig. 2, the vertical displacement of the vehicle to the right, , cZ 、 1tZ 、 2tZ respectively body, front and
rear bogie vertical displacement, c 、 1t 、 2t respectively front and rear bogie nod corner, 1wZ 、 2wZ 、 3wZ 、
4wZ respectively for the first one, two, three and four of the vertical displacement.
According to Lagrange equation for vehicle dynamics model is derived and its kinetic equation written in
compact form as follows:
M Z C Z K Z F , (1)
In the formula: Z is the displacement matrix, M is the mass matrix, K is the stiffness matrix, C is the
damping matrix, F is the force matrix for the wheel. In the matrix Z , 1dZ 、 2dZ 、 3dZ 、 4dZ are the vertical
displacement of the dynamic vibration absorber corresponding to the corresponding wheel is represented.
= r FF C q K q , (2)
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
r
r
r
r
r
C
C
C
C
C
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
r
r
r
r
r
K
K
K
K
K
, (3)
Dynamic vibration absorber
3. Study on Vibration Reduction Effect of the Rail Vehicle with Axle Dynamic Vibration Absorber
www.ijres.org 14 | Page
III. MODEL SOLVING
The Fourier transform (1) is performed in the frequency domain:
12
H M j C K F
, (4)
Since the excitation of each wheel has a certain delay, the input of the three wheel is considered as the input of
the first wheel.
Wheels by incentive matrix:
1 2 3 4 1( ) ( ) ( ) ( ) ( )
T
q q q q Q q , (5)
In the formula: 1 ( )q 、 2 ( )q 、 3 ( )q 、 4 ( )q respectively, the excitation of the four wheels in the frequency
domain.
Including:
32 4
= 1
Tj Tj T j T
Q e e e
, (6)
In the formula 2 2 tT l u , 3 2 cT l u , 4 2 t cT l l u .
It can be obtained that the frequency response matrix of each part of the vehicle is not smooth, and each element
of the matrix is the frequency response function of the displacement of the vehicle.
1 14=
T
h H Q h h , (7)
According to the frequency response function of the displacement, the acceleration response function can be
obtained.
1
2 2
1
i
i
iZ q
Z
h h
q
, (8)
1 1
2
1i i
Z q Z q
G h q
, (9)
In the formula: 1iZ q
h is the acceleration frequency response function of the corresponding component
relative to the irregularity excitation is expressed, 1iZ q
G is the acceleration power spectral density of the
corresponding components for the irregularity excitation is indicated.
Although the acceleration power spectral density can be very convenient to analyze the frequency characteristics
of vertical vibration of vehicle system, the acceleration of vertical vibration of the vehicle in the frequency range
of 1 to n frequency range is required:
1
1
2n
ii zG G d
, (10)
IV. SIMULATION RESULTS
4.1 MODEL PARAMETERS
Based on one type of vehicle as an example, According to the dynamic vibration absorber principle
can determine the dynamic vibration absorber absorbing quality and stiffness, the parameters are shown in Table
1, With American class six track irregularity spectrum as incentive of the vehicle vertical vibration model.
Table1 A certain type of vehicle parameters and track parameters
Meaning Parameter symbol Value
Mass of vehicle Mb/kg 4.18×104
Car body pitch inertia Jb/(kg·m2) 1.686×106
Mass of bogie Mt/kg 2.8×103
Bogie pitch inertia Jt/( kg·m2) 1.93×103
Secondary spring stiffness per bigie Ks2/( kN·m-1) 6×105
Secondary damping per bogie Cs2/( kN·s·m-1) 1.1×104
Primary spring stiffness per axle Ks1/( kN·m-1) 1.11×106
Primary spring damping per axle Cs1/( kN·s·m-1) 2.4×104
Half of bogie centers lb/m 9
Half of bogie wheel base lw/m 1.25
Mass of Dynamic vibration absorber Md/kg 140
Dynamic vibration absorber stiffness Kd/( kN·m-1) 4×105
Dynamic vibration absorber damping Cd/( kN·s·m-1) 50
4. Study on Vibration Reduction Effect of the Rail Vehicle with Axle Dynamic Vibration Absorber
www.ijres.org 15 | Page
4.2 PERFORMANCE ANALYSIS OF DYNAMIC VIBRATION ABSORBER
To simulate the model and obtain the components of the vehicle vertical vibration acceleration power
spectral density.
Fig.3 Effect of dynamic vibration absorber on the vibration of wheel set
The wheel vertical acceleration power spectral density curves of vibration is as shown in Fig. 3, It can be
seen from Fig. 3 that the wheel's vertical vibration at 40Hz with excitation frequency resonance and reached
peak. Therefore, the wheel vibration is most intense, resulting in damage to the wheel strength, seriously
affecting the safe operation of the vehicle. After installing the dynamic vibration absorber, vertical vibration of
the wheel has been significantly reduced in the resonance frequency.
Wheel vertical vibration is passed primary suspension up to the bogie, The wheel vibration directly affects
the vibration situation of the bogie, the Front and rear bogie vertical acceleration power spectral density curves
of vibration is as shown in Figure 4, It can be seen from Fig. 4 thatdue to the wheels produce resonance in 40Hz,
leading to the bogie at 40Hz also produces vibration peak, dynamic vibration absorber reduce the vertical
vibration of wheel at the resonant frequency, Vertical vibration transmitted to the bogie has been weakened,
Therefore, the axle dynamic vibration absorber can not only reduce the wheel vertical vibration can also weaken
the vertical vibration of the bogie.
(a) Front bogie
PSDofFrontbogie/m2s-3
f /Hz
f /Hz
PSDofWheelset/m2s-3 No DVA
With DVA
5. Study on Vibration Reduction Effect of the Rail Vehicle with Axle Dynamic Vibration Absorber
www.ijres.org 16 | Page
(a) Rear bogie
Fig.4 The influence of dynamic vibration absorber on the vibration of bogie
The car body vertical acceleration power spectral density curves of vibration is as shown in Fig. 5, It can be
seen from Fig.5 that due to bogie vertical vibration in the vicinity of 40Hz is weakened, so the vertical vibration
of the vehicle body vibration at this frequency is also weakened. However, the body's natural frequency of about
1.5Hz, body vertical vibration of the energy is concentrated at low frequencies near the natural frequency. The
vibration energy is smaller in the near of 40Hz frequency. Therefore, although the dynamic vibration absorber
can reduce vibration here, the effect of reduce the vehicle's vertical vibration is limited
Fig.5 Effect of dynamic vibration absorber on the vibration of car body
The wheel has a good vertical vibration damping effect on the wheel. In order to improve the vibration
performance, the mass ratio of the dynamic vibration absorber is improved. Fig. 6 shows the influence of the
mass ratio of the dynamic vibration absorber on the vibration absorption performance of the dynamic absorber.
The mass ratio of the dynamic vibration absorber can obviously improve the vibration reduction performance.
Moreover, the vibration frequency band of the dynamic vibration absorber is gradually widened.
PSDofCarbody/m2s-3
f /Hz
PSDofRearbogie/m2s-3
f /Hz
6. Study on Vibration Reduction Effect of the Rail Vehicle with Axle Dynamic Vibration Absorber
www.ijres.org 17 | Page
Fig.6 Influence of mass ratio on the vibration reduction effect of dynamic vibration absorber
V. CONCLUSIONS
Axle vibration absorber for vertical vibration of the wheel not only has a good inhibition, but also on the
bogie and the body has a important damping effect. For the vertical vibration of the vehicle body is mainly
concentrated in the low frequencies, therefore, the axle dynamic vibration damping effect on the body is limited.
The vibration reduction effect can be improved by increasing the mass ratio of the axle dynamic vibration
absorber. The vibration of the wheel is radiated from the outside; therefore, the vibration of the axle can be
controlled by reducing the vertical vibration of the wheel.
VI. ACKNOWLEDGEMENTS
The authors would like to acknowledge the support of National Natural Science Foundation of China (Grant
No. 11472176), Natural Science Foundation of Shanghai (Grant No. 15ZR1419200) and Discipline
Construction Project for Transportation Engineering (Grant No. 13SC002).
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[3] FOO E,GOODALL R M.Active Suspension Control of Flexible-Bodied Railway Vehicle Using Electro-Hydraulic and
Electromagnetic Actuators[J].Control Engineering Practice,2000,8:507-518.
[4] ZENG Jing;WU Ping-bo;HAO Jian-hua.Analysis of Vertical Vibration Reduction for Railway Vehicle Systems [J]. China
Railway Science, 2006,27(3):62-67.
[5] ZHOU Jinsong ZHANG Wei SUN Wenjing .Vibration Reduction Analysis of the Dynamic Vibration Absorber on the Flexible
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No DVA
μ=0.003
μ=0.015
f /Hz
PSDofWheelset/m2s-3