关键词: 动力学, 反馈控制, 球形机器人, 双偏心质量块, 工业机器人, 激光跟踪仪, 位姿精度, 在线补偿

Abstract: A spherical robot driven by two pendulums is designed, which is actuated by both the eccentric force and the inertial force generated by the inner drive unit when the robot is in motion. Because of the point contact between spherical shell and ground, the friction cannot counteract the change of motion state caused by motion error of inner drive unit when the robot is in a switching process between static configuration and dynamic configuration. A linear motion control method of two-pendulums-driven spherical robot is studied for the stable start-stop and speed control. The dynamic model of linear motion is constructed by Lagrange equation. A Gaussian function based smooth trajectory control method for linear motion is proposed through analysis of the relationship among dynamic parameters, and the correctness of the method is verified theoretically by simulation. A feedback controller of linear motion is designed to guarantee the accurate tracking of the expected value of practical control signals. The effectiveness of the controller is validated by simulation and prototype experiment.

Key words: Dynamics, Feedback control, Spherical robot, Two pendulums, industrial robots, laser tracker, online compensation, positioning and attitude accuracies