基于无源观测器的机器人笛卡尔空间力/阻抗控制方法研究

许多由机器人完成的任务都需要机器人与外部环境接触。在如抛光、去毛刺和装配作业中都需要执行精确的力控制。由于环境模型的不准确在力控制过程中当机器人与环境脱离接触时可能与周围环境发生激烈碰撞。针对此问题提出了基于无源观测器的力控算法。通过分析系统无源性, 研究了笛卡尔空间力/阻抗控制的稳定条件。发现只有力控制器的输出会破坏系统的无源性，根据系统无源性的分析结果设计了使用无源性观测器的力/阻抗控制器。在MATLAB仿真环境中对力/阻抗控制控制算法和基于无源性观测器的力/阻抗控制进行仿真验证。仿真结果表明基于无源性观测器的力/阻抗控制器在机器人末端工具与环境脱离接触时能够有效降低机械臂移动速度，减小对周围环境的冲击力。

Passivity Monitor based Cartesian Force/Impedance Control Method Study

Many tasks completed by robots require robots to contact the external environment. Precise force control is required in polishing, deburring and assembly operations. Due to the inaccuracy of the environment model, the robot may collide violently with the surrounding environment when it is out of contact with the environment in the process of force control. Aiming at this problem, a force control algorithm based on passivity monitor is proposed. The stability condition of Cartesian space force / impedance control is studied by analyzing the passivity of the system. It is found that only the output of the force controller will destroy the passivity of the system. According to the analysis results of the passivity of the system, a passivity monitor based cartesian force/impedance control is designed. The force / impedance control algorithm and force / impedance control based on passivity monitor are simulated and verified in MATLAB simulation environment. The simulation results show that the passivity monitor based cartesian force/impedance control can effectively reduce the moving speed of the manipulator and the impact on the surrounding environment when the end tool of the robot is out of contact with the environment.