Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24529
J. Deur, J. Asgari, D. Hrovat
A dynamic tire friction model based on the comprehensive LuGre friction model has been proposed recently for the case of pure longitudinal motion. An extension of the model for combined longitudinal and lateral motion, including calculation of the self aligning torque, is presented in this paper. The extended model is derived for both uniform and non-uniform normal pressure distributions. The model steady-state behavior is validated with respect to Pacejka static tire model, which served as an “ideal” benchmark. Possible further improvements of the proposed model are also addressed.
{"title":"A Dynamic Tire Friction Model for Combined Longitudinal and Lateral Motion","authors":"J. Deur, J. Asgari, D. Hrovat","doi":"10.1115/imece2001/dsc-24529","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24529","url":null,"abstract":"\u0000 A dynamic tire friction model based on the comprehensive LuGre friction model has been proposed recently for the case of pure longitudinal motion. An extension of the model for combined longitudinal and lateral motion, including calculation of the self aligning torque, is presented in this paper. The extended model is derived for both uniform and non-uniform normal pressure distributions. The model steady-state behavior is validated with respect to Pacejka static tire model, which served as an “ideal” benchmark. Possible further improvements of the proposed model are also addressed.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81412970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24569
J. Brown, M. Franchek
Presented in this paper is a model-based method for assessing suspension and motor health of washing machines. The diagnosis of the suspension and motor health is achieved by processing the measured dynamics of the washtub. In particular, an online adapted lumped parameter model of the washtub is used to estimate key suspension and motor parameters. These parameters are identified from the measured displacement of the washtub due to a motor pulse input prior to the beginning of the wash cycle. Comparing the estimated values to design values assesses both suspension and motor health. Included are simulation results to validate the parameter estimation process.
{"title":"Washing Machine Health Diagnostics Through Information Synthesis","authors":"J. Brown, M. Franchek","doi":"10.1115/imece2001/dsc-24569","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24569","url":null,"abstract":"\u0000 Presented in this paper is a model-based method for assessing suspension and motor health of washing machines. The diagnosis of the suspension and motor health is achieved by processing the measured dynamics of the washtub. In particular, an online adapted lumped parameter model of the washtub is used to estimate key suspension and motor parameters. These parameters are identified from the measured displacement of the washtub due to a motor pulse input prior to the beginning of the wash cycle. Comparing the estimated values to design values assesses both suspension and motor health. Included are simulation results to validate the parameter estimation process.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84704462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, the dynamic performance of an unconventional two-spool flow control servo valve using a pressure control pilot is analyzed. Such valves are less expensive than typical servo-valves but also tend to be limited in their dynamic performance. Based on a previously developed eight state nonlinear model, we develop a simplified linear model which is able to capture the essential dynamics of the valve. Using root locus analysis method, the limitation in dynamic performance is shown to be due to a “zero” introduced by the structure of the interconnection of the subsystems. Design parameters that move the “zero” further to the left half plane, and do not adversely affect other steady state criteria are identified. The effectiveness of these parameters to improve the dynamic performance is demonstrated.
{"title":"Dynamic Redesign of a Flow Control Servo-Valve Using a Pressure Control Pilot","authors":"Perry Y. Li","doi":"10.1115/1.1485288","DOIUrl":"https://doi.org/10.1115/1.1485288","url":null,"abstract":"\u0000 In this paper, the dynamic performance of an unconventional two-spool flow control servo valve using a pressure control pilot is analyzed. Such valves are less expensive than typical servo-valves but also tend to be limited in their dynamic performance. Based on a previously developed eight state nonlinear model, we develop a simplified linear model which is able to capture the essential dynamics of the valve. Using root locus analysis method, the limitation in dynamic performance is shown to be due to a “zero” introduced by the structure of the interconnection of the subsystems. Design parameters that move the “zero” further to the left half plane, and do not adversely affect other steady state criteria are identified. The effectiveness of these parameters to improve the dynamic performance is demonstrated.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"135 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85009821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24575
Cheng-Lun Chen, G.T.-C. Chiu
In this paper, a repetitive control based 2 degree-of-freedom (DOF) controller for a SISO motor/gear-train system is proposed. Instead of sequential design, it is shown that the optimal 2 DOF controller for such system can be obtained simultaneously by solving an mixed-sensitivity problem. The simulation results are presented to show the feasibility and effectiveness of the proposed control structure for periodic and non-periodic disturbance reduction for motor/gear-train velocity regulation.
{"title":"Disturbance Rejection Using Two Degree of Freedom Repetitive Control Through Mixed Sensitivity Optimization","authors":"Cheng-Lun Chen, G.T.-C. Chiu","doi":"10.1115/imece2001/dsc-24575","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24575","url":null,"abstract":"\u0000 In this paper, a repetitive control based 2 degree-of-freedom (DOF) controller for a SISO motor/gear-train system is proposed. Instead of sequential design, it is shown that the optimal 2 DOF controller for such system can be obtained simultaneously by solving an mixed-sensitivity problem. The simulation results are presented to show the feasibility and effectiveness of the proposed control structure for periodic and non-periodic disturbance reduction for motor/gear-train velocity regulation.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85050465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24545
Samuel Y. Chang, Christopher R. Carlson, J. Gerdes
Model reduction based upon the idea of eliminating coordinates with low levels of associated power, energy or activity has been proposed by a number of researchers. None of these results, however, produce the sort of computable bounds on the neglected dynamics that would be useful in the design of controllers with guaranteed robustness properties. This paper outlines an approach to model reduction based upon Lyapunov functions that represent a modified version of the system energy of Lagrangian subsystems. The Lyapunov functions are used to bound the states of subsystems to be removed, enabling these states to be treated as time-varying perturbations in a simplified set of dynamic equations. In contrast to other results in energy-based model reduction, this approach provides bounds on the disturbances caused by the unmodeled dynamics though at the cost of the implementation ease associated with other methods.
{"title":"A Lyapunov Function Approach to Energy Based Model Reduction","authors":"Samuel Y. Chang, Christopher R. Carlson, J. Gerdes","doi":"10.1115/imece2001/dsc-24545","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24545","url":null,"abstract":"\u0000 Model reduction based upon the idea of eliminating coordinates with low levels of associated power, energy or activity has been proposed by a number of researchers. None of these results, however, produce the sort of computable bounds on the neglected dynamics that would be useful in the design of controllers with guaranteed robustness properties. This paper outlines an approach to model reduction based upon Lyapunov functions that represent a modified version of the system energy of Lagrangian subsystems. The Lyapunov functions are used to bound the states of subsystems to be removed, enabling these states to be treated as time-varying perturbations in a simplified set of dynamic equations. In contrast to other results in energy-based model reduction, this approach provides bounds on the disturbances caused by the unmodeled dynamics though at the cost of the implementation ease associated with other methods.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89648375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24598
B. Song, A. Howell, K. Hedrick
In this paper, a method of analyzing the performance loss caused by faults that effect the longitudinal control of an automated vehicle is presented. First, a hybrid longitudinal controller based on Dynamic Surface Control (DSC) is developed to provide robust stabilization. Then, ellipsoidal approximations of the tracking error bounds are obtained via convex optimization for the nonlinear closed-loop system. The bounds are then used to design a fault classification scheme and fault management system based on the amount of performance loss as measured by a quadratic Lyapunov function. Simulation results of the fault tolerant controller are shown for both single and multiple multiplicative faults.
{"title":"Robust Fault Classification and Handling for Longitudinal Vehicle Control","authors":"B. Song, A. Howell, K. Hedrick","doi":"10.1115/imece2001/dsc-24598","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24598","url":null,"abstract":"\u0000 In this paper, a method of analyzing the performance loss caused by faults that effect the longitudinal control of an automated vehicle is presented. First, a hybrid longitudinal controller based on Dynamic Surface Control (DSC) is developed to provide robust stabilization. Then, ellipsoidal approximations of the tracking error bounds are obtained via convex optimization for the nonlinear closed-loop system. The bounds are then used to design a fault classification scheme and fault management system based on the amount of performance loss as measured by a quadratic Lyapunov function. Simulation results of the fault tolerant controller are shown for both single and multiple multiplicative faults.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82875659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24509
D. Garg, Manish Kumar
This paper presents the formulation and application of a genetic algorithm based strategy for the determination of an optimal trajectory for a multiple robotic configuration. First, the motivation for multiple robot control and the current state-of-art in the field of cooperating robots are briefly given. This is followed by a discussion of energy minimization techniques in the context of robotics, and finally, the principles of using genetic algorithms as an optimization tool are included. The initial and final position of the end effector are specified. Two cases, one of a single manipulator, and the other of two cooperating manipulators carrying a common payload illustrate the approach proposed. The genetic algorithm identifies the optimal trajectory based on minimum joint torque requirements. The minimization of a suitably defined performance index involving joint torques implies that the trajectory thus obtained requires the least amount of torque.
{"title":"Optimal Path Planning and Torque Minimization via Genetic Algorithm Applied to Cooperating Robotic Manipulators","authors":"D. Garg, Manish Kumar","doi":"10.1115/imece2001/dsc-24509","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24509","url":null,"abstract":"\u0000 This paper presents the formulation and application of a genetic algorithm based strategy for the determination of an optimal trajectory for a multiple robotic configuration. First, the motivation for multiple robot control and the current state-of-art in the field of cooperating robots are briefly given. This is followed by a discussion of energy minimization techniques in the context of robotics, and finally, the principles of using genetic algorithms as an optimization tool are included. The initial and final position of the end effector are specified. Two cases, one of a single manipulator, and the other of two cooperating manipulators carrying a common payload illustrate the approach proposed. The genetic algorithm identifies the optimal trajectory based on minimum joint torque requirements. The minimization of a suitably defined performance index involving joint torques implies that the trajectory thus obtained requires the least amount of torque.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"49 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80531798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24621
Vicente Parra‐Vega
Robotic teleoperation is a difficult task because of the inherent difficulty to model and control time-delay nonlinear models. In order to handle tractable models, typically there have been two ways to tackle this problem: i) The first approach is to assume that the system is fast enough and thus the time delay can be neglected, in this way time-delay-free differential equations are obtained such that the controller is time-delay-free. This approach needs further formal study to validate this assumption, and so far there is neither strict nor rigorous result that support this claim, when considering the full nonlinear telerobotic dyanmics. ii) In the second approach, the time delay is considered explicitly, however typically nonlinear dynamics is neglected and then linear models are used to derive time-delay-based control systems. The second approach ignores that the robots are nonlinear systems with strong nonlinear inertial couplings, and therefore controllers based on linear time-delay models render low performance. In this paper, the teleoperation of robots is modeled, including nonlinear dynamics in the continuous domain, without any time delay, and model-based nonlinear continuous second order sliding mode controllers are proposed which guarantee finite-time convergence. Thus, this approach attempts to propose a scheme for the second approach outlined above. The teleoperation system provides force reflection to the human operator, and a kinematic-based predictive display yields visual stimuli while the master robot yields kinesthetic feedback to the operator to allow planning better desired trajectories, including contact forces, in contrast to other predictive displays that have been proposed in the literature. Therefore, the theoretical foundations of finite-time convergent telecontrol system and its advantages are discussed.
{"title":"Time Delay-Free Nonlinear Bilateral Teleoperation With Model-Based Predictive Display","authors":"Vicente Parra‐Vega","doi":"10.1115/imece2001/dsc-24621","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24621","url":null,"abstract":"\u0000 Robotic teleoperation is a difficult task because of the inherent difficulty to model and control time-delay nonlinear models. In order to handle tractable models, typically there have been two ways to tackle this problem: i) The first approach is to assume that the system is fast enough and thus the time delay can be neglected, in this way time-delay-free differential equations are obtained such that the controller is time-delay-free. This approach needs further formal study to validate this assumption, and so far there is neither strict nor rigorous result that support this claim, when considering the full nonlinear telerobotic dyanmics. ii) In the second approach, the time delay is considered explicitly, however typically nonlinear dynamics is neglected and then linear models are used to derive time-delay-based control systems. The second approach ignores that the robots are nonlinear systems with strong nonlinear inertial couplings, and therefore controllers based on linear time-delay models render low performance. In this paper, the teleoperation of robots is modeled, including nonlinear dynamics in the continuous domain, without any time delay, and model-based nonlinear continuous second order sliding mode controllers are proposed which guarantee finite-time convergence. Thus, this approach attempts to propose a scheme for the second approach outlined above. The teleoperation system provides force reflection to the human operator, and a kinematic-based predictive display yields visual stimuli while the master robot yields kinesthetic feedback to the operator to allow planning better desired trajectories, including contact forces, in contrast to other predictive displays that have been proposed in the literature. Therefore, the theoretical foundations of finite-time convergent telecontrol system and its advantages are discussed.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82964071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24587
Fan Wang, Shaoqiang Dong, K. Danai, D. Kazmer
An adaptation method is investigated for improving the shape of input profiles in injection molding. The noted characteristic of injection molding is that performance feedback (i.e., part quality measure) becomes available only at the end of the cycle, therefore, the performance of the entire sequence of inputs that form the profile is evaluated by the same delayed measure at the end of the cycle. The proposed profiling method uses the concept of reinforcement learning, which is particularly suited to problems with delayed feedback. For an initial study, the method is tested in improving the profiles of the ram velocity and packing pressure. For this study, a simulation program is used to provide estimates of digital video disks (DVDs) quality attributes as feedback for evaluating the performance of the adapted profiles. The initial results indicate that the proposed method is effective in refining the profiles, which will lead to better quality parts with faster cycles.
{"title":"Input Profiling for Injection Molding by Reinforcement Learning","authors":"Fan Wang, Shaoqiang Dong, K. Danai, D. Kazmer","doi":"10.1115/imece2001/dsc-24587","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24587","url":null,"abstract":"\u0000 An adaptation method is investigated for improving the shape of input profiles in injection molding. The noted characteristic of injection molding is that performance feedback (i.e., part quality measure) becomes available only at the end of the cycle, therefore, the performance of the entire sequence of inputs that form the profile is evaluated by the same delayed measure at the end of the cycle. The proposed profiling method uses the concept of reinforcement learning, which is particularly suited to problems with delayed feedback. For an initial study, the method is tested in improving the profiles of the ram velocity and packing pressure. For this study, a simulation program is used to provide estimates of digital video disks (DVDs) quality attributes as feedback for evaluating the performance of the adapted profiles. The initial results indicate that the proposed method is effective in refining the profiles, which will lead to better quality parts with faster cycles.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"112 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81007835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/dsc-24578
Dong-Jun Lee, M. Tomizuka
In this paper, the use of an accelerometer in precision motion control of linear motors is investigated. The acceleration measurement can provide several advantages. In particular, it can be used with the position measurement for estimation of the position and velocity based on a kinematic model. It can be further utilized for identification of dynamic parameters such as coulomb friction and cogging force as well as for estimation of disturbance. Experimental results verify the effectiveness of the proposed estimation/identification schemes. These schemes are integrated into a two-degree of freedom control system for precision motion control of linear motors. The proposed schemes are evaluated by experiments performed on a linear permanent-magnet motor.
{"title":"State/Parameter/Disturbance Estimation With an Accelerometer in Precision Motion Control of a Linear Motor","authors":"Dong-Jun Lee, M. Tomizuka","doi":"10.1115/imece2001/dsc-24578","DOIUrl":"https://doi.org/10.1115/imece2001/dsc-24578","url":null,"abstract":"\u0000 In this paper, the use of an accelerometer in precision motion control of linear motors is investigated. The acceleration measurement can provide several advantages. In particular, it can be used with the position measurement for estimation of the position and velocity based on a kinematic model. It can be further utilized for identification of dynamic parameters such as coulomb friction and cogging force as well as for estimation of disturbance. Experimental results verify the effectiveness of the proposed estimation/identification schemes. These schemes are integrated into a two-degree of freedom control system for precision motion control of linear motors. The proposed schemes are evaluated by experiments performed on a linear permanent-magnet motor.","PeriodicalId":90691,"journal":{"name":"Proceedings of the ASME Dynamic Systems and Control Conference. ASME Dynamic Systems and Control Conference","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89276048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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