基于力/位混合控制的机器人打磨

Robot Grinding Based on Force/Position Hybrid Control

为了研究打磨机器人在作业时的位置与法向力控制问题,在目前非恒力打磨的情况下,提出了位置与法向力配合控制打磨的方法。实现打磨的过程分为接触打磨、轨迹恒力打磨、凸起长效打磨。传统的力控制为基于伺服位置环的方式,在此基础上还进行了基于速度伺服的力/位混合控制方式研究。在基于速度环的控制方式上进行了基于末端传感器的力/位混合控制策略研究。对比传统机器人打磨方式,该控制方式在保持较高法向力控性能的基础上,还将末端力的反馈用于切向的位置控制,进一步提升了力控与位控性能。并对速度环的速度、位置环的位置两个量与末端传感器的力进行了转换关系求解,对力、位控制闭环反馈关系进行阐述并进行阶跃响应与正弦响应仿真,验证了该力控方法对打磨机器人的控制性能。

In order to study the position and normal force control of the grinding robot during operation, a method of controlling grinding based on position and normal force was put forward under the current non-constant force grinding condition. The process of grinding could be divided into three parts: contact grinding, trajectory constant grinding, and protruding long-effect grinding. The traditional force control was based on servo position loop. On this basis, there was an analysis of hybrid force/position control method based on velocity servo. In this paper , based on the velocity loop control method, the hybrid force/position control strategy based on the end sensor was studied. Compared with the traditional robot grinding method, the control method not only maintains high normal force control performance, but also uses the feedback of end force for tangential position control, which further improves the performance of force control and position control. The method also solves the conversion relationship between the speed and position of the speed loop and the force of the end sensor. The closed-loop feedback relationship of the force and position control is elaborated and the step response and sinusoidal response are simulated to verify the control performance of the force control method for the grinding robot.