Coupling worm gears in large machine tool manipulator units (axes) can lead to overload damages under some operating conditions, like asymmetrical driving and emergency stop. This behaviour is caused by the self locking characteristic of worm gears with small pitch. If operated in the direction opposite to the designated one, self-locking can occur in the gears, subjecting the gears to an arbitrary torque which can be destructive. This condition can occur without counter torque on the driving side. In most gears, tooth engagement is based on a rolling motion. The slip component increases with a growing axis angle between the paired gears. In case of worm gears, the axis angle is 90_, and therefore the coupling is purely frictious.This friction coupling is important in modelling. Especially the transition between the static and dynamic friction, where the system parameters change abruptly by a factor of two, should not be neglected.Based on the evaluated model a synchronous controller has been developed. This controller gives the oppertunity to drive swiveling axes with coupled selflocking gears by a standard gantry topology with an overlayed state changing master-slave topology
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Springs - DESIGN OF MACHINE ELEMENTS-IIDr. L K Bhagi
Introduction to springs, Types and terminology of springs, Stress and deflection equations, Series and parallel connection, Design of helical springs, Design against fluctuating load, Concentric springs, Helical torsion springs, Spiral springs, Multi-leaf springs, Optimum design of helical spring
Bearingless Permanent Magnet Synchronous Motor using Independent ControlIJPEDS-IAES
Bearingless permanent magnet synchronous motor (BPMSM) combines the
characteristic of the conventional permanent magent synchronous motor and
magnetic bearing in one electric motor. BPMSM is a kind of high
performance motor due to having both advantages of PMSM and magnetic
bearing with simple structure, high efficiency, and reasonable cost. The
research on BPMSM is to design and analyse BPMSM by using Maxwell 2-
Dimensional of ANSYS Finite Element Method (FEM). Independent
suspension force model and bearingless PMSM model are developed by
using the method of suspension force. Then, the mathematical model of
electromagnetic torque and radial suspension force has been developed by
using Matlab/Simulink. The relation between force, current, distance and
other parameter are determined. This research covered the principle of
suspension force, the mathematical model, FEM analysis and digital control
system of bearingless PMSM. This kind of motor is widely used in high
speed application such as compressors, pumps and turbines.
A review on design and development of eccentric shaft for cottonLaukik Raut
The present review provides brief information about
the design of eccentric shaft for cotton ginning
machine. The author suggest that, significant of
eccentric shaft are as follows,
1. Due to the small eccentric distance in design of
eccentric shaft; friction torque is very small, which
result in small friction loss and high system
efficiency.
2. The torque acted on motor increased as eccentric
distance expanded which result in poor force
condition and complicate structure.
3. Eccentric shaft are usually with features of small
eccentric distance, thus its can only provide small
displacement.
Eccentric shaft is the important element, which play
the important role in ginning operation. These shafts
provide an oscillatory motion or action to moving
knives. Eccentric shaft is required in various
industries according to their application. In
traditional case, implementation of the proper
selection of raw material, latest and advance
methodologies is typical task.
Examination of parametric linkages reveals that
eccentric shaft life is dependent on load acting on the
eccentric shaft, its geometry, metallurgical properties
and wear. Today in design and development of
eccentric shaft by using the good quality of raw
material that is alloy steel with composition of Fe
(98.5%), Al (0.5%), C (0.5%), and Mo (0.5%) by
using that composition the life of eccentric shaft is
increases. latest and advance methodologies for
ginning machine increases productivity and high
quality of operation is possible
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Springs - DESIGN OF MACHINE ELEMENTS-IIDr. L K Bhagi
Introduction to springs, Types and terminology of springs, Stress and deflection equations, Series and parallel connection, Design of helical springs, Design against fluctuating load, Concentric springs, Helical torsion springs, Spiral springs, Multi-leaf springs, Optimum design of helical spring
Bearingless Permanent Magnet Synchronous Motor using Independent ControlIJPEDS-IAES
Bearingless permanent magnet synchronous motor (BPMSM) combines the
characteristic of the conventional permanent magent synchronous motor and
magnetic bearing in one electric motor. BPMSM is a kind of high
performance motor due to having both advantages of PMSM and magnetic
bearing with simple structure, high efficiency, and reasonable cost. The
research on BPMSM is to design and analyse BPMSM by using Maxwell 2-
Dimensional of ANSYS Finite Element Method (FEM). Independent
suspension force model and bearingless PMSM model are developed by
using the method of suspension force. Then, the mathematical model of
electromagnetic torque and radial suspension force has been developed by
using Matlab/Simulink. The relation between force, current, distance and
other parameter are determined. This research covered the principle of
suspension force, the mathematical model, FEM analysis and digital control
system of bearingless PMSM. This kind of motor is widely used in high
speed application such as compressors, pumps and turbines.
A review on design and development of eccentric shaft for cottonLaukik Raut
The present review provides brief information about
the design of eccentric shaft for cotton ginning
machine. The author suggest that, significant of
eccentric shaft are as follows,
1. Due to the small eccentric distance in design of
eccentric shaft; friction torque is very small, which
result in small friction loss and high system
efficiency.
2. The torque acted on motor increased as eccentric
distance expanded which result in poor force
condition and complicate structure.
3. Eccentric shaft are usually with features of small
eccentric distance, thus its can only provide small
displacement.
Eccentric shaft is the important element, which play
the important role in ginning operation. These shafts
provide an oscillatory motion or action to moving
knives. Eccentric shaft is required in various
industries according to their application. In
traditional case, implementation of the proper
selection of raw material, latest and advance
methodologies is typical task.
Examination of parametric linkages reveals that
eccentric shaft life is dependent on load acting on the
eccentric shaft, its geometry, metallurgical properties
and wear. Today in design and development of
eccentric shaft by using the good quality of raw
material that is alloy steel with composition of Fe
(98.5%), Al (0.5%), C (0.5%), and Mo (0.5%) by
using that composition the life of eccentric shaft is
increases. latest and advance methodologies for
ginning machine increases productivity and high
quality of operation is possible
ANALYSIS OF FRICTION INDUCED VIBRATION DURING ENGAGEMENT OF CLUTCHESIAEME Publication
Safety aspect in automotive engineering is of prime importance and given priority in design and development of vehicle. This vehicle development needs to meet safety requirement. Braking system along with good suspension systems, good handling and safe cornering, is one of the most critical system in the vehicle. The objective of this work is to design, analyze and investigate the temperature distribution of rotor disc during braking operation using suitable numerical tools. The numerical study uses the finite element analysis techniques to predict the temperature distribution on the full and ventilated brake disc. This analysis is further used to identify the critical temperature of the rotor by varying geometric design of the disc. The analysis also gives us, the heat flux distribution for the disc rotors with various groove patterns.
Stress Analysis of I.C.Engine Connecting Rod by FEM and PhotoelasticityIOSR Journals
Abstract: The automobile engine connecting rod is a high volume production critical component. Every vehicle
that uses an internal combustion engine requires at least one connecting rod .From the viewpoint of
functionality, connecting rods must have the highest possible rigidity at the lowest weight. The major stress
induced in the connecting rod is a combination of axial and bending stresses in operation. The axial stresses are
produced due to cylinder gas pressure (compressive only) and the inertia force arising in account of
reciprocating action (both tensile as well as compressive), where as bending stresses are caused due to the
centrifugal effects. The result of which is, the maximum stresses are developed at the fillet section of the big and
the small end.Hence, the paper deals with the stress analysis of connecting rod by Finite Element Method using
Pro/E Wildfire 4.0 and ANSYS WORKBENCH 11.0 software. The comparison and verification of the results
obtained in FEA is done experimentally by the method of Photo elasticity(Optical Method). The method of
Photoelasticity includes the casting of Photoelastic sheet using Resin AY103 and Hardner HY951, preparation
of the model from Photoelastic sheet calibration of the sheet to determine material fringe value.
Keywords - Big End fillet section ,Connecting Rod, Compressive Stresses , Failure of Connecting Rod, FEA,
Photoelasticity, Small End fillet section, Tensile Stresses.
This is a short description and some problems for the design of clutches.This also include the various classification in clutch and its description,use and also advantages of using these kinds of clutches.
It also includes a short view through different types of numerical problems which are solved for practising.
This is a Major Project Report successfully done at DVRCET under the guidance of Mechanical Engineering Department & the Managing Director of NIRAJA TECHNOLOGIES located at Uppal (Hyderabad).
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Identification of dynamic rigidity for high speed spindles supported on ball ...eSAT Journals
Abstract The widespread use of high-speed machining in recent decades has led to a significant area of research on issues that limit its productivity. Regenerative chatter is a well‐known machining problem that results in unstable cutting process, leads to the poor surface quality, reduced material removal rate and damage on the machine tool itself. The main requirement for the stability of system dynamics is the information of tool tip frequency response functions (FRF’s).The present work considered a coupled model of spindle-bearing system by using the angular contact ball bearing forces on stability of machining. Using Timoshenko beam element formulation, the spindle unit is analyzed by including the gyroscopic and centrifugal terms and the bearing contact forces are arrived from Hertzian contact theory. Then, the model is used for studying the effects of viscous damping to obtain the tool point FRF for the dynamic spindle. Index Terms: Spindle dynamics, Stability, High speed effects, Bearing contact forces, Hertzian contact theory, Finite element modeling.
PREDICTIONS AT THE BLOW END OF THE LD-KGC CONVERTER BY A SEMI-DYNAMIC CONTROL...ijmech
The decision to perform direct turn-down or not, based on an accurate estimate of temperature at the blow end, prevents two types of problems: (a) the loss of productivity due to the wait time in the steelmaking; and (b) tapping of off-specification heat.
In the present work, a technique and model for temperature prediction at the blow end are briefly discussed, along with their limitations and perspectives for application. As a result of this analysis, a mathematical model based in heat and mass balances has been developed with a view to evaluating the possibility of improving this prediction capability. The formulation of said model and its preliminary adjustment to industrial data are presented and discussed, and the main limitations and difficulties in the application of the methodology are highlighted.
The study here presented focuses the development of a semi-dynamic control model in the LD-KGC converter (Linz-Donawitz-Kawasaki Gas Control Converter). The control model enables one to predict the temperature of the blow end by solving both the energy and mass equations. The computational language adopted is Fortran 90; the equations are solved iteratively until a solution for temperature is found. The inputs to the control model are the load data of the LD-KGC converter at the blow beginning and the collected data by the lance to 89% of oxygen blow. The results obtained in the present work were compared to the data measured in steel making. The semi-dynamic control model results agree well with data for LDKGC converters. However, the model is sensitive to the premises here adopted, like those pertaining to the exit gas composition (CO and CO2).
EFFECT OF PROCESS PARAMETERS ON SURFACE ROUGHNESS OF NICKEL BASED ALLOYS IN WEDMijmech
In contrast to conventional machining process, WEDM may be proved more economic and efficient in
precise machining of wide range of materials ranging from die steel to the high temperature resistance
super alloys. In this study, the effect of WEDM process parameters like peak current (Ip), pulse on time
(Ton), pulse off time (Toff) and servo voltage (V) on the surface roughness has been considered while
machining of Nimonic 90 and Monel 400 using Taguchi’s method. Using Taguchi’s L18 orthogonal array,
process parameters were investigated for surface roughness. Analysis of variance shows that Ton and Ip
are highly significant process parameters for surface roughness.
ANALYSIS OF FRICTION INDUCED VIBRATION DURING ENGAGEMENT OF CLUTCHESIAEME Publication
Safety aspect in automotive engineering is of prime importance and given priority in design and development of vehicle. This vehicle development needs to meet safety requirement. Braking system along with good suspension systems, good handling and safe cornering, is one of the most critical system in the vehicle. The objective of this work is to design, analyze and investigate the temperature distribution of rotor disc during braking operation using suitable numerical tools. The numerical study uses the finite element analysis techniques to predict the temperature distribution on the full and ventilated brake disc. This analysis is further used to identify the critical temperature of the rotor by varying geometric design of the disc. The analysis also gives us, the heat flux distribution for the disc rotors with various groove patterns.
Stress Analysis of I.C.Engine Connecting Rod by FEM and PhotoelasticityIOSR Journals
Abstract: The automobile engine connecting rod is a high volume production critical component. Every vehicle
that uses an internal combustion engine requires at least one connecting rod .From the viewpoint of
functionality, connecting rods must have the highest possible rigidity at the lowest weight. The major stress
induced in the connecting rod is a combination of axial and bending stresses in operation. The axial stresses are
produced due to cylinder gas pressure (compressive only) and the inertia force arising in account of
reciprocating action (both tensile as well as compressive), where as bending stresses are caused due to the
centrifugal effects. The result of which is, the maximum stresses are developed at the fillet section of the big and
the small end.Hence, the paper deals with the stress analysis of connecting rod by Finite Element Method using
Pro/E Wildfire 4.0 and ANSYS WORKBENCH 11.0 software. The comparison and verification of the results
obtained in FEA is done experimentally by the method of Photo elasticity(Optical Method). The method of
Photoelasticity includes the casting of Photoelastic sheet using Resin AY103 and Hardner HY951, preparation
of the model from Photoelastic sheet calibration of the sheet to determine material fringe value.
Keywords - Big End fillet section ,Connecting Rod, Compressive Stresses , Failure of Connecting Rod, FEA,
Photoelasticity, Small End fillet section, Tensile Stresses.
This is a short description and some problems for the design of clutches.This also include the various classification in clutch and its description,use and also advantages of using these kinds of clutches.
It also includes a short view through different types of numerical problems which are solved for practising.
This is a Major Project Report successfully done at DVRCET under the guidance of Mechanical Engineering Department & the Managing Director of NIRAJA TECHNOLOGIES located at Uppal (Hyderabad).
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Identification of dynamic rigidity for high speed spindles supported on ball ...eSAT Journals
Abstract The widespread use of high-speed machining in recent decades has led to a significant area of research on issues that limit its productivity. Regenerative chatter is a well‐known machining problem that results in unstable cutting process, leads to the poor surface quality, reduced material removal rate and damage on the machine tool itself. The main requirement for the stability of system dynamics is the information of tool tip frequency response functions (FRF’s).The present work considered a coupled model of spindle-bearing system by using the angular contact ball bearing forces on stability of machining. Using Timoshenko beam element formulation, the spindle unit is analyzed by including the gyroscopic and centrifugal terms and the bearing contact forces are arrived from Hertzian contact theory. Then, the model is used for studying the effects of viscous damping to obtain the tool point FRF for the dynamic spindle. Index Terms: Spindle dynamics, Stability, High speed effects, Bearing contact forces, Hertzian contact theory, Finite element modeling.
PREDICTIONS AT THE BLOW END OF THE LD-KGC CONVERTER BY A SEMI-DYNAMIC CONTROL...ijmech
The decision to perform direct turn-down or not, based on an accurate estimate of temperature at the blow end, prevents two types of problems: (a) the loss of productivity due to the wait time in the steelmaking; and (b) tapping of off-specification heat.
In the present work, a technique and model for temperature prediction at the blow end are briefly discussed, along with their limitations and perspectives for application. As a result of this analysis, a mathematical model based in heat and mass balances has been developed with a view to evaluating the possibility of improving this prediction capability. The formulation of said model and its preliminary adjustment to industrial data are presented and discussed, and the main limitations and difficulties in the application of the methodology are highlighted.
The study here presented focuses the development of a semi-dynamic control model in the LD-KGC converter (Linz-Donawitz-Kawasaki Gas Control Converter). The control model enables one to predict the temperature of the blow end by solving both the energy and mass equations. The computational language adopted is Fortran 90; the equations are solved iteratively until a solution for temperature is found. The inputs to the control model are the load data of the LD-KGC converter at the blow beginning and the collected data by the lance to 89% of oxygen blow. The results obtained in the present work were compared to the data measured in steel making. The semi-dynamic control model results agree well with data for LDKGC converters. However, the model is sensitive to the premises here adopted, like those pertaining to the exit gas composition (CO and CO2).
EFFECT OF PROCESS PARAMETERS ON SURFACE ROUGHNESS OF NICKEL BASED ALLOYS IN WEDMijmech
In contrast to conventional machining process, WEDM may be proved more economic and efficient in
precise machining of wide range of materials ranging from die steel to the high temperature resistance
super alloys. In this study, the effect of WEDM process parameters like peak current (Ip), pulse on time
(Ton), pulse off time (Toff) and servo voltage (V) on the surface roughness has been considered while
machining of Nimonic 90 and Monel 400 using Taguchi’s method. Using Taguchi’s L18 orthogonal array,
process parameters were investigated for surface roughness. Analysis of variance shows that Ton and Ip
are highly significant process parameters for surface roughness.
tcStatistical and regression analysis of vibration of carbon steel cutting to...ijmech
Machining is a convoluted process in which many variables can deleterious the desired results. Among them, cutting tool vibration is the most decisive phenomenon which influences dimensional precision of the components machined, functional behavior of the machine tools and life of the cutting tool. In a machining operation, cutting speed, depth of cut and the tool feed rate principally influence cutting tool vibrations. In this paper, effects of cutting speed, feed rate and depth of cut on cutting tool vibration in both the directions, i.e. axial and tangential are investigated by the statistical methods of signal to noise ratio
(SNR), analysis of variance (ANOVA) and regression analysis. Experiments have been conducted using the L9 orthogonal array in the centre lathe machine. Carbon steel was selected as cutting tool materials to conduct the experiments. From experimental results, the amplitude of vibration of the cutting tool was ascertaining for each machining performance criteria. The significance and percentage contribution of each parameter were determined by Analysis of variance (ANOVA).It has been observed that cutting speed has a maximum contribution on cutting tool vibration in both the directions. Variation of the vibration of cutting tool with machining parameters was mathematically modeled by using the regression analysis
method. The predicted value from the developed model and experimental values are found to be very close
to each other justifying the significance of the model. Confirmation runs demonstrates that the optimized result and the values obtained through regression analysis are within the prescribed limit
Comparison of fuzzy logic and neural network for modelling surface roughness ...ijmech
Surface roughness is the main indicator of technological performances of a component for electrical discharge machining (EDM). EDM process of manganese alloyed cold-work tool steel was modelled. In this paper we used the fuzzy logic (FL) and neural network (NN) to predict the effect of machining variables (discharge current and pulse duration) on the surface roughness of manganese alloyed cold-work tool steel in order to improve and increase its range of application. The experiments are carried out on
manganese alloyed cold-work tool steel, processed with electrodes made of copper. The values of surface
roughness predicted by these models are then compared. All models show good agreement with experimental results. When compared to the NN and FL models, the NN model has shown a significant forecast improvement. The results indicate that the NN model is an effective algorithm to forecast the surface roughness in EDM.
The development of high performance material such as composites and advanced ceramics has a variety of
manufacturing challenges. It is known that many of these materials cannot be effectively machined by conventional machining methods. Apart from economics, the process selection is based on the machined surface integrity. The high pressure waterjet with abrasive additives known as abrasive water jet (AWJ) is one viable alternative to conventional processing and has been suggested for use in post mold shaping of composites and other hard to cut material. The research works on water jet cutting is discussed in this paper. Omni directional cutting potential as well as minimal thermal and mechanical loading are few
advantages. There are several parameters influencing the performance of abrasive water jet machining. Important process parameters which mainly affect the quality of cutting are traverse speed, hydraulic pressure, abrasive flow rate, standoff distance, and abrasive type, work material. Material removal rate(MRR) and surface roughness (Ra), taper of cut, width of cut are important quality parameters of AWJM.
techDynamic characteristics and stability of cylindrical textured journal bea...ijmech
The dynamic characteristics of cylindrical textured hydrodynamic journal bearing are presented in this paper. The Reynolds equation is solved numerically in a finite difference grid in an iterative scheme satisfying the appropriate boundary conditions. Stiffness and damping coefficients of fluid film and stability parameter are found using the first-order perturbation method for different eccentricity ratios and various texture parameters like texture depth and texture density.. From the present analysis, it has been found that stability is enhanced with increase in texture depth, whereas there is an optimum texture density corresponding to the maximum stability of the bearing
Design of quick connect disconnect hydraulic couplingijmech
Quick Connect-Disconnect Couplings (QCDCs) provide a means of rapidly disconnecting a fluid line without loss of hydraulic fluid or entrance of air into the system. They are most commonly used for hydraulic systems in aerospace applications like space stations, launch vehicles, etc. Information regarding the design of QCDCs is not available in open literature. This paper details the preliminary design and optimization of QCDCs for indigenization of the technology, and the general configuration arrived at. A
QCDC consists of two halves – a male half and a female half. The sealing action is achieved by using poppet valve in the male half and a moveable sleeve in the female half. O-rings are used to ensure that the design is leak-proof. Changes in pressure and velocity of the fluid flowing through the QCDC have been kept to a minimum by ensuring gradual changes in cross-section wherever possible.
LAB SCALE PREPARATION AND EVALUATION OF YTTRIA STABILIZED ZIRCONIA THERMAL BA...ijmech
Ceramic based coatings are routinely being engineered to protect metallic components from high
temperature environments in applications like gas turbines and jet engines. However, although a wellresearched
technology, detailed and realistic information on the effects of thermal barrier coatings (TBCs)
in improving the performance of commercial diesel engines is either classified or inconsistent. Additional
information by means of lab scale and analytical evaluation of TBCs prepared from 8%Y2O3-ZrO2 plasma
sprayable powders (prepared in the laboratory by using organic binders), coated onto aluminium
substrates, corroborated by simulation model is one part of this paper. The findings are supplemented by
studying the influence of the TBCs on aluminium pistons in a single cylinder nine horsepower class diesel
engine, thereby carrying out realistic performance of the engine involving parameters such as Power
(Brake, Indicated and Frictional), thermal efficiency, fuel consumption, effects of ceramic insulation on
emission and exhaust temperature and peak cylinder pressure, as the concluding part of the studies.
SENSITIVITY ANALYSIS OF NANO-NEWTON CMOS-MEMS CAPACITIVE FORCE SENSOR FOR BIO...ijmech
In this research, we investigated about sensitivity of a Nano-Newton CMOS-MEMS capacitive force sensor.Sensitivity analysis is an important factor to reach a more optimized structure for MEMS force sensors and improve their efficiency. The procedure is based on scaling rules of the electrodes. The most change of capacitance (increased capacitance + decreased capacitance) occurs in =2/3. By this , gap, w (thickness of metals) and L (the length of comb fingers) become 2 (μm), 0.46 (μm) and 66.67 (μm) respectively. In this case, sensitivity of increased capacitance and decreased capacitance are 0.0585 fF/nN (8.33% increase) and 0.09 fF/nN (2.27% increase) respectively. By combining all the results, it can be obtained to increase w and L and decrease gap (g) simultaneously which consequently leads to 1.2×w, 1.2×L and 2/3×gap.Such results show sensitivity for increased capacitance is 0.19 fF/nN (251.85% increase) and for decreased capacitance is 0.3 fF/nN (240.9% increase).. by these selections, length (L), thickness of metal (w) and gap become 120 (μm), 0.828 (μm) and 2 (μm) respectively.
DIMINUTION OF TEMPERATURE FLUCTUATION INSIDE THE CABIN OF A HOUSEHOLD REFRIGE...ijmech
This work shows the effect phase change material (PCM) on temperature fluctuation inside the evaporator cabinet of a household refrigerator. The experiment has been done at different thermal loads with two different PCMs (Water and Eutectic solution (90% H2O + 10% NaCl) of melting point 0°C and -5°C respectively). The PCM is placed around the five sides of the evaporator cabinet in which the evaporator coil is immersed. The experimental results with PCM confirm the notable reduction of the fluctuation of the cabin temperature at lower load but at higher load this effect is not so significant. Between two PCM, the reduction of temperature fluctuation for Eutectic solution is better than water PCM. This reduction of temperature fluctuation ultimately improves the food preservation quality of the refrigerator
Designing, implementation, evolution and execution of an intelligent manufact...ijmech
This paper shows a framework of the different techniques for the design of the planning and governing components, implementation, Evolution and execution of an intelligent manufacturing system. Architecture of a modern manufacturing industry is presented, which makes possible to create specific manufactrons system for the specific tasks, depending on the self-operated analysis of its essential characteristics. The manufactronic industry concept helps in the integration of intelligence and to increase flexibility at the maximum level of the manufacturing system as well as at the minimum level of the particular machine. This concept is implemented & demonstrated in the automobile and aeronautical industries, but can be simply applied to nearly all manufacturing industries. Implementation of manufactronic techniques in the industries helps to forecast and to fulfill the rapidly varying customer requirements, to produce high
quality products in sufficient quantities with reduction in costs. The Modern Intelligence Technologies are
also presented in this paper.
THE EFFECT OF GEOMETRICAL PARAMETERS ON HEAT TRANSFER AND HYDRO DYNAMICAL CHA...ijmech
Compact size and high heat transfer coefficient of helical coil heat exchangers causes them to have an
important role in various industrial applications. This paper investigate numerically on the influence of
different parameters such as coil radius, coil pitch and diameter of tube on the hydrodynamic and
heat transfer characteristics of helical double tube heat exchangers using the CFD software which is
based on the principles of heat transfer, fluid mechanics and thermodynamics. The results indicated that
heat transfer augmentation occurs by increasing of the inner Dean Number, inner tube diameter, curvature
ratio and by the reduction of the pitch of heat exchanger coil. By increasing the radius of coils, the
secondary flow effects due to centrifugal forces diminishes and flow of fluid through the coils tends to flow
in a straight path and as a result, the friction coefficient decreases consequently.
Precision robotic assembly using attractive regionsijmech
This paper describes a method for peg-in-hole insertion based on attractive regions a new approach to decompose 6D configuration space into two 3D subspaces. An impedance controller, in combination with the attractive regions, is integrated in a novel controller whereby human-like assembly performance is achieved without using a force sensor. In this paper, the insertion task uses three different pegs, as shown in Fig. 1. The strategy is to decompose the 6 DOF space in which the peg moves into two low-dimensional subspaces. The controller uses stereo-triangulation and a k nearest-neighbor (k-NN) algorithm to identify the parts. An impedance controller monitors the forces (estimated by motor current rather than a force transducer) applied to the system and uses events rather than time to determine the state and the evolution
of the assembly process. The approach is experimentally verified using a Barrett Technology’s WAM Arm,
a backdrivable 7 DOF robotic manipulator
VISION ALGORITHM FOR SEAM TRACKING IN AUTOMATIC WELDING SYSTEMijmech
Arc welding is an important technology for joining metals and repairing metal products in manufacturing
industries. It is usually performed by a skilled worker. Due to the shortage of skilled workers and due to the
hazardous and unpleasant working conditions, the automation of arc welding is gaining importance
nowadays. Existing welding robots require that the dimensions, position and orientation to be programmed
prior to the process. These robots suffer from an evident lack of flexibility. This paper presents an
automatic welding system assisted by a machine vision system to compute the dimension, position and
orientation of the workpieces. By analysing the image taken by the camera, a simple algorithm is developed
to detect the dimension, position and orientation of the workpieces. The calculated data is then fed to a
controller which controls the welding electrode movement. Use of machine vision system has eliminated the
need to pre feed the workpiece data to the robot and hence the system is made flexible.
Smart fluid self adaptive damper system (sfsads)ijmech
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ELECTRONIC SYNCHRONOUS SHAFT FOR SWIVEL AXES DRIVEN BY COUPLED SELFLOCKING WORMGEAR DRIVES
1. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
1
ELECTRONIC SYNCHRONOUS SHAFT FOR
SWIVEL AXES DRIVEN BY COUPLED
SELFLOCKING WORMGEAR DRIVES
Christian Preiser1
, Andreas Fink2
and Oliver Zirn3
1
Institut of Process and Production Control Technology, Technical University of
Clausthal, Clausthal-Zellerfeld, Germany
2
Rückle GmbH Werkzeugfabrik, Römerstein, Germany
3
Pforzheim University, Pforzheim, Germany
ABSTRACT
Coupling worm gears in large machine tool manipulator units (axes) can lead to overload damages under
some operating conditions, like asymmetrical driving and emergency stop. This behaviour is caused by the
self locking characteristic of worm gears with small pitch. If operated in the direction opposite to the
designated one, self-locking can occur in the gears, subjecting the gears to an arbitrary torque which can
be destructive. This condition can occur without counter torque on the driving side. In most gears, tooth
engagement is based on a rolling motion. The slip component increases with a growing axis angle between
the paired gears. In case of worm gears, the axis angle is 90_, and therefore the coupling is purely
frictious.This friction coupling is important in modelling. Especially the transition between the static and
dynamic friction, where the system parameters change abruptly by a factor of two, should not be neglected.
Based on the evaluated model a synchronous controller has been developed. This controller gives the
oppertunity to drive swiveling axes with coupled selflocking gears by a standard gantry topology with an
overlayed state changing master-slave topology
KEYWORDS
coupled selflocking gears, swivel axis, synchronous controller, electronic synchron shaft, worm gear
1 INTRODUCTION
Machining of large and heavy workpieces by using machine tools with more than three axes
increases steadily. Multiple axes milling, for example, reqiures not only motion of the tools or
translation of workpieces but also rotary motions of workpieces. Rotary axes for moving
workpieces are often implemented as swivel axes, rotary tables, or as combinations of both. Most
of the implemented swivel axes and rotary tables nowadays are driven by using spur gear drives
or worm gear drives [12]. For this research paper, dealing with coupled selflocking gear driven
axes, rotary tables, and swivel axes can be treated similarly. They just differ in the stiffnes
between both drives.So in this research, swivel axes will be treated representatively and rotary
2. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
2
tables will be reduced to swivel axes with high bridge stiffness. Due to low drive torque, single
drive driven axes are often not able to handle heavyweight loads with the required dynamics.
They also do not allow accurate
Figure 1. General view IPP testbed
machining while in motion [6]. The elastic drive chain leads to loss of accuracy and an increased
influence of the process forces on the positioning accuracy at the processing point (TCP, tool
center point). Together with gear backlash, chatter can also occur, which results in chatter marks
on the machined surface, as described in [8]. To reduce these problems, distributed parallel acting
actuators are used, which increase the input value, improve axis stiffness, and reduce
backlash.The reduction, or, ideally, the elimination of backlash increases the precision, enabling
processing without first clamping the axis and thus enabling machining while the axis is moving.
This slack compensation can be performed by interlocking the two actuators of an axis and is
generally torque-controlled. Among axes with distributed drives, predominantly drives with non-
self-locking spur-gears can be found, as there is currently no way of operating axes with self-
locking drives safely and non-destructively. Pretension with self-locking, coupled drives is not
feasible using torque control. Due to the high rigidity of worm gears, a combination of worm
gears with theconcept of distributed drives is expected to result in a remarkable gain in stiffness.
Figure 1 shows the testbed used in the experiments.
2 STATIC AND DYNAMIC FRICTION IN STRAIGHT-WEDGE
MECHANISMS
For illustration purposes, the worm gear in this study will be modelled as the related wedge-type
mechanism. Using this model, the pheomena of the worm gear can be presented.
3. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
3
Figure 2. 3D view of straight-wedge mechanism with pressure angle
Figure 3. Straight wedge mechanism 2D cutaway view with force settings
The two superposed wedges with a twofold inclined plane thereby replace the tooth contact with
the pressure angle n and the pitch angle m. The equivalent image reduced to two dimensions in
Fig.3 contains all the necessary parameters for modeling [11], [3]. The tooth surface normal force
is calculated from a deflected spring damper unit, as shown in Fig.5, that models the elastic tooth
contact with backlash. Based on this axial force the internal friction FR can be determined based
on the system states. This internal friction is responsible for the self-locking behavior of
gearboxes with high ratios.
4. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
4
Figure 4. Friction cone
Graphically, this situation is presented by the friction cone presented in in Fig.4. If the force of
the load force vector is within this cone, friction is dominant, and the system stops. Based on this
graph, the difference between self-locking gears and self-braking gears can also be explained. If
the force vector is found within the smaller red cone as a result of the pitch angle i.e. it is within
the dynamic friction cone, friction prevails in each system state and the gear comes to a halt in the
absence of the driving force FA and independent of the external load force. The system is self-
braking. If the force vector is within the range outside the red and inside the blue cone, the system
in a moving state does not necessarily come to a stop. However, if the system remains at rest, the
system will remain in this state regardless of the external load force. In this paper, worst-case
estimate is used to examine only the case of self-braking gears.
3 OPERATION OF COUPLED GEARS
If one applies the above considerations to the system shown in Fig.5, it is clear that torque-
controlled pretensioning of outgoing-side mechanically-coupled self-locking drives can not be
realized. Here, the backlash-free spring damper unit presented between the two gear units is a
simplified equivalent mechanical diagram of the bridge. If one side of the pivot axis is driven, no
statement can be made about the second gear, if the applied driving force results from internal
friction and causes pretenssioning, or if the driving force originates from an additional internal
friction force. This means that the contacting flank is not uniquely identifiable. Furthermore, the
friction coefficients are not known with sufficient accuracy, so that the tooth flank normal force
cannot be computed based on the driving forces. It in any case, information about the deflection
of the spring-damper units is necessary.
5. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
5
Figure 5. Coupled straight wedge mechanism schema of couppled worm gears
By implication, this means that the pretensioning can be set by adjusting the offset of the two
drives with respect to each other. Thus, it is possible to realize a control scheme modeled on the
mechanical balance shaft between two drives. Instead of a simple torque pretensioning, a drive-
dependent differential torque addition is realized (see Fig.6). This concept can also be used, as
opposed to the previously used control topologies such as gantry or master-slave, to compensate
unbalanced operating conditions such as a drive failure or unevenly distributed loads or
transmission parameters.
4 SYNCHRONOUS CONTROLLER
The implementation of the synchronous controller in the form of a difference-dependent torque
overlay is shown schematically in Fig.6 and Fig.7 and comes up to an electronic implementation
of a mechanical synchron shaft or balancer shaft which where used in the past for synchronisation
problems [7] and [9].
Figure 6. Synchronous controller concept shown at straight wedge mechanism
6. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
6
Figure 7. Synchronous controller schema
The controller consists of a standard P-PI cascade controller for each drive and is operated in a
gantry topology as described in [4], [10], [12] and [13]. Each drive gets the same nominal
values.In addition, there is an superposed P-PI controller, which, based on the drive deviation
error ev, outputs a torque set point which is added to the controller output current of the laging
motor and is subtracted from the controller output current of the leading motor. Additionaly, the
controller outputs are weighted with increasing drive positioning difference , so that the influence
of the normal axis control over the weighting function 1-ev.kgv is reduced from 1 to 0 and the
influence of the synchronous controller of the weighting function ev.kgv is increased from 0 to 1.
The weighting function kgv is arbitrary and defines the sensitivity and responsiveness of the
synchronous controller to the drive difference. However, it has been shown however that a
function with continuous transitions of the controller stability is conducive. Accordingly, the
initial quadratic weighting function with a progressive response was replaced by a sinusoidal
function (Fig.8).
Figure 8. Multiple weighting functions
7. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
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Figure 9. Controller model schema with synchronous controller
This controller assembly with conventional P-PI cascade controllers allows the topology to be
implemented on industrial controllers and to facilitate the commissioning by using known
technologies.Successful implementation was done on a Siemens Sinamics S120 drive system with
a Siemens CU320-2DP as a control unit. The controller implementation was carried out under the
Siemens software package Simotion Scout by creating the control structure in Drive Control
Charts.The following measurements are realized by an dSPACE realtime control system with the
synchronous controller implementation shown in Fig.9.
5 SIMULATIONS AND MEASUREMENTS
The most fatal unbalance to be handled is a breakdown of one drive. Therefore the drive
breakdown scenario has been defined as a standard test for synchronous controller topologies.
Simulation results and measurements, carried out in a research of Nathanael Bach [1] and [2],
show that the developed controller works in priciple. But the stable area for the possible
weighting gain parameters of the synchrounous controller and the axes controllers, which has to
be defined manually, is very small, so that the controller cannot be called robust.
The drive differential angle gain, which defines the gradient of the used weighting functions, is
the most sensitive controller parameter. It scales the maximum drive difference to one. This
parameter has to be smaller than the maximum possible elastic tension remaining after the user
defined pretension. Stable operation can be expected with one half of possible tension reserve.
Exceeding this value causes the drives to lock.
8. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
8
Figure 10. Simulated operation with drive break down in not pretensioned operating mode
(a) Detail: Drive break down,not pretensioned (b) [Detail: Set value crossing in negativ direction,
not pretensioned
9. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
9
Figure 11. Details from figure 10
By using correct adjusted parameters, the controller holds the position with the maximum
predefined pretension. Because the setpoints of the differential controller are calculated from
drive positions of an inertial system, no setpoint steps are expected. The setpoint curve can be
treated as quasiacceleration-limited. By using the overlayed synchronous controller, each of both
drives acts on the errors of the other and so limits the maximum possible drive position difference
to the predefined maximum value, even if one drive breaks down. In fault cases this behaviour
possibbly causes setpoint differences from the NC-setpoints but on the other hand leads to a
reduction of normal tooth forces in the gears and prevents the wormgears from damage. To
predict axes behaviour, a scalable axis simulation model has been developed and combined with a
discrete controller model by using the software packages Matlab and Simulink. The principle of
this model is an coulombic friction model to represent the static and dynamic friction of the real
system. The implementation is founded on an example of H.A. Gall [5]. The model has been
verified on the IPP testbed and on a large swivelaxis system from Rückle GmbH. The
measurement and simulation results show a very big compliance and so the simulation results
could be expanded to other swivel axes and rotary tables.
The measurement data in Fig.11 show in detail fragments of the trajectory driven without
pretensioning(Fig.10). The curve setup is a drive breakdown of drive one at 6.95 sec. The
subfigures(b) and (c) show the setpoint trajectory crossing the actual position, accompanied by
master drive changing. The still active drive follows the given curve by doubled predefined
pretension angle kgv up to the inverted controller balance. After reactivation of the failed drive,
both drives are going back to the given path and will follow it. This option will not be used on
reality, because due to that the predefined maximum motion speed for the axis will be set for
driving to actual setpoints and in that zone no path accuracy will be given. In case of an error a
10. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
10
controlled system emergency stop,which forces an synchronous drive shut down, hast to be
initiated. Only after reaching a complete halt the drives can be switched off.
Figure 12. Simulated operation with drive break down in pretensioned operating mode
11. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
11
Figure 13. Details from figure (12)
The illustration Fig.12 shows the same experiment as used in Fig.10 but in this case tensed up.
This test also proves, in simulations as well as in practice, that the controller keeps the
synchronization.While drive failure occures, the active drive of the tensed operation mode driven
testbed oscillates a bit more than in not tensed state. This behaviour is founded in the internal
friction. The missing backlash area, which could be used as control range, causes instantly rising
normal and friction forces. The system time constant has been reduced without increasing the
controller performance.Nervertheless the oscillation amplitudes of the drive position differences
are between approx. 0.5 times of the allowed differences and therefore at max. 75% of the
remaining tension reserve. By that the essential working of the controller is shown.
Considering the corresponding simulated tooth flank normal forces of an pretensioned system in
case of a simulated drive break down shows a force reduction of 80% by using the synchronous
controller compared to the standard gantry controller (see Fig.14 and Fig.15). In cases of non
pretensioned operation, reduction factors of 95% are reachable.
12. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
12
Figure 14. Normal force characteristic during drive break down for different operation states at the IPP-
Test bed, operating without synchronous controller
13. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
13
Figure 15. Normal force characteristic during drive break down for different operation states at the IPP-
Testbed, operating with synchronous controller
So, the tooth flank normal forces don’t exceed the operation range or the design range and thus a
damage free operation is possible. When operating the axes with coupled selflocking drives
without the synchronous controller, a drive break down can’t be handled and the axis seizes.
Caused by the static friction value of 0.18, which is compared to the dynamic friction value of
0.07 more than 2 times higher, as well as the system dynamics, the locked axis can’t be relieved
by the motor torque.The extremly high normal forces and the thereby displaced lubricant increase
the static friction value additionally. The probability of scuffing, broken teeth of the wheel and
bronze weldings to the worm is quite high.
6 Emergency Shut Down
As described above for handling a drive fault savely, the system has to be shut down controlled
by the remaining activ drive. The required electrical power can be pulled from the grid. But to
handle a grid fault, no external power can be used. So power errors like electrical power outage or
14. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
14
a power breakdown after emergency power-off switch has been used is much more critical to
catch. In this cases, were no electrical power can be consumed from the grid, the power has to be
provided by the link capacity until the system halts.
Figure 16. Simulated link power consumption of used testbeds while controlled emergency stop
The plots in Fig.16 show a simulated emergency shut down after one drive breaked and coasts
down freely. This experiment gives an appraisal of the effective required shut down energy. Here
is to be considered that the system is able to regenerate and so the required energy is just the
integral of power over shut down time. Caused by the selflocking characteristic, the controlled
drive has just to overcome the system’s friction. Thereby the total power consumption is quite
low and, under ideal conditions, amounts just 0.04 Ws for the IPP-Testbed and about 100Ws for
the real axes. Caused by the higher internal friction, pretensioned operation increases the power
consumption depending on the drive offset and has to be removed when an power supply error
occurs. For real systems the efficiency factor of the regeneration, the drives and the controller has
to be considered as well, so that the real used energy is some higher. With an estimated
consumption factor of two and two active drives each consuming the same, the used energy is 4
times higher and has to be considered at dimensioning the link capacitor.
15. International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.3, No.1, February 2014
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7 CONCLUSIONS
Using axes with distributed self-inhibitive actuation and pretension have apparently
advantages.But the benefit of the high stiffness and the lower backlash of worm gears in
comparison to multistage spur gears cannot be completely used. A simple backlash compensation
by using additional drive torques, which is used with spur gears, is not implementable for worm
gears. A backlash compensation applied to wormgears is just realisable by adding position
differences to the drives.Because of small accepted drive position deviations, each controlled
system in reality has some deviations from the setpoints, a position difference tollerance range is
necessary. This range has to be as small as possible, but so wide that neither pretension is
removed nor axes tension gets such high, that the drives jam. That needs a minimum flexibility
between both drives, favourably located in the bridge, that reduces the whole axis stiffnes and
thereby in parts the advantages of using wormgears. The necessary minimum flexibility of the
bridge depends on internal system clock therewith from the synchronous controller stiffness. In
actual control units the system clock is so slow that, caused by the synchronous control loops
time constants, the bridge stiffnes and controller dynamic had to be reduced severely.
An additional disadvantage of backlash reduced or backlash compensated operation of
wormgears is founded in the friction. During pretensioned operation the tooth flanks are touching
each with no controlled normal force.With a torque controlled pretension in spur gears, the
normal forces are proportional to the pretension torque. By using position controlled pretension in
worm gears, extremly rised tooth flank normal forces caused by geometrical deviations and
position difference errors can occure. In connection with the high sliding ratio of the motion
between tooth contact surfaces in worm gears, the already high abrasion increases additionally. In
addition to the geometrical errors thermical effects have consequences to the backlash and
therefor to the normal forces. That means, that for operation of axes, driven by coupled
selflocking gears, a position depending and temperature compensated pretension angle control is
needed to limit this disturbing influences. Due to the high abrasion a frequent identification of
axis backlash over the worm gear wheel girth is needed to creat an actual backlash look-up-table
which is needed for automaticaly generated presets for backlash compensation. Besides the
lifetime of the gear is reduced and service costs increase.Therefore a protected axes operation of
coupled self locking drives is possible, but because of the high abrasion a pretensioned operation
should not be used.
8 ACKNOWLEDGMENT
The results presented in this paper have been worked out in the AIF/ZIM project
KF2081601WD8 founded by the Federal Ministry of Economics and Technology
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Authors
Name: Oliver Zirn
Affiliation: Professor, Dr. habil., Pforzheim University, Pforzheim, Germany
Professor Zirn studied electrical engineering at the Stuttgart University and recieved
his PhD in mechanical engineering at the ETH Zurich in 1996. He worked as
development engineer in machine tool industry and became a private lecturer for
machine tool mechatronics at the ETH Zurich in 2008.Since 2013 he is Professor for Automotive
Mechatronics at the Pforzheim University.
Name: Christian Preiser
Affiliation: Dipl.-Ing., Institut of Process and Production Control Technology,Technical
University of Clausthal, Clausthal-Zellerfeld, Germany
Dipl.-Ing. Christian Preiser studied machanical engineering at the Technical University
of Clausthal. Since 2009 he is research assistant at the Institut of Process and Production
Control Technology at the Technical University of Clausthal and works on the applied research of coupled
wormgear drive control issues.
Name: Dipl.-Ing. (FH) Andreas Fink
Affiliation: Dipl.-Ing. (FH), team leader assembly, machine tool manufacturer Rückle
GmbH, Römerstein, Germany
Dipl.-Ing. (FH) Andreas Fink studied Automation Technology at the Giessen University
of Applied Sciences. Since 2007 he is assembly team leader at the machine tool
manufacturer Rückle GmbH in Römerstein, Germany, and works on the applied research of advanced servo
control issues.