Minimum-time trajectory control of a two-link flexible robotic manipulator

An analysis is made of the experimental results of a minimum-time trajectory control scheme for a two-link flexible robot. An offline optimization routine determines a minimum-time, straight-line tip trajectory which stays within the torque constraints of the motors and ends with no vibrational transients. An efficient finite-element model is used in the optimization to approximate the flexible arm dynamics. The control strategy described is used to determine the feedback gains for the position, velocity, and strain gage signals from a quadratic cost criterion based on the finite-element model linearized about the straight-line tip trajectory. These feedback signals are added to the modeled torque values obtained from the optimization routine and used to control the robot arm actuators. The results indicate that this combination of model-based and error-driven control strategies, achieves a closer tracking of the desired trajectory and a better handling of modeling errors than either strategy alone.<<ETX>>

[1]  Stephen Yurkovich,et al.  Acceleration feedback for control of a flexible manipulator arm , 1988, J. Field Robotics.

[2]  Christopher G. Atkeson,et al.  Experimental evaluation of feedforward and computed torque control , 1987, IEEE Trans. Robotics Autom..

[3]  Umit Ozguner,et al.  An analysis of distributed vibration control of flexible manipulators using integral manifolds , 1989, Proceedings of the 28th IEEE Conference on Decision and Control,.

[4]  G. R. Eisler,et al.  Approximate Minimum-Time Trajectories for Two-link Flexible Manipulators , 1990, 1990 American Control Conference.

[5]  Rush D. Robinett,et al.  Model-based damping of coupled horizontal and vertical oscillations in a flexible rod , 1991, J. Intell. Robotic Syst..

[6]  Takeo Kanade,et al.  Parameter identification of robot dynamics , 1985, 1985 24th IEEE Conference on Decision and Control.

[7]  Bruno Siciliano,et al.  A Singular Perturbation Approach to Control of Lightweight Flexible Manipulators , 1988, Int. J. Robotics Res..

[8]  Neil C. Singer,et al.  Residual Vibration Reduction in Computer controlled Machines , 1989 .

[9]  Farshad Khorrami.  Analysis of multi-link flexible manipulators via asymptotic expansions , 1989, Proceedings of the 28th IEEE Conference on Decision and Control,.

[10]  J. Tlusty,et al.  Feedforward and feedback control of a flexible robotic arm , 1990, IEEE Control Systems Magazine.

[11]  J.T. Feddema,et al.  Integration of model-based and sensor-based control for a two-link flexible robot arm , 1990, 1990 IEEE International Conference on Systems Engineering.