Nonlinear robust industrial robot control.

摘要

Manufacturing tasks often require short cycle time and consistent quality. To meet these demands, a robot control system must achieve fast and precise robot position control, and/or maintain proper force control at the robot's end-effector. Many control schemes were proposed in the literature for robot position control formulated in either joint or cartesian coordinates. Some robot control schemes were also proposed for hybrid (force and position) control in the cartesian coordinate. Nevertheless, when uncertainties such as modeling errors or unknown external disturbances exist, performance of these schemes substantially degrades.;These nonlinear robust control schemes were applied to a two-joint SCARA-type robot through computer simulation. The results demonstrate that these schemes exhibit excellent robustness properties and can achieve satisfactory robot position or force control under severe modeling errors.;This dissertation proposes a nonlinear robust control methodology for robot control under the influence of uncertainties. The control input consists of a nonlinear part and a linear part. The nonlinear part decouples a robot dynamics and obtains a set of equations in joint or hand coordinates. The linear part utilizes robust servo-mechanism theory to suppress position or force tracking error in each respective coordinate. Based on this nonlinear robust control concept, the following schemes for robust robot control are proposed: (1) A nonlinear robust control scheme for robot position control in joint coordinates. (2) A nonlinear robust control scheme for robot position control in cartesian coordinates. (3) A nonlinear robust control scheme for robot hybrid control in cartesian coordinates.