磨抛机器人气电力控末端执行器负载特性研究

针对现有船舶制造业中人工打磨或砂带磨削等磨抛作业难以满足智能制造需求的现状,提出一种面向船舶磨抛机器人的气电混合式力控末端执行器,采用自适应变参数PID控制器对非对称气缸的气动力与大推力永磁直线同步电机的电磁力进行协调控制,实现作业接触力的实时补偿与精确控制。通过对气动系统、永磁直线同步电机系统、环境工件、力和速度控制器等进行建模与数值仿真,研究其负载波动响应与抗负载冲击特性。仿真结果表明,相比气动力控系统,气电混合式力控系统可消除气动系统振荡特性的影响,在35Hz范围内振动负载作用下的最大力波动幅值由138N(约为稳态值46%)减小至25N(约为稳态值8.4%)；在阶跃负载作用下气缸活塞杆位移振荡和接触力冲击次数显著减少,调整时间分别仅为前者的32.3%和27.3%,有效提高了抗负载波动与冲击特性,可提升船舶磨抛机器人作业质量。

Research on Load Characteristics of Pneumoelectric End-effector with Force Control for Grinding and Polishing robot

For the unfitness of manual or abrasive belt grinding for intelligent manufacturing in shipbuilding industry, a novel pneumoelectric end-effector for grinding and polishing robot is proposed. Pneumatic force of asymmetric cylinder and electromagnetic force of Permanent Magnet Linear Synchronous Motor (PMLSM) were coordinated by adaptive variable parameter PID controller to achieve real-time compensation and precise control of the contact force during the operation of robotic grinding and polishing. Through modeling and simulation analysis of pneumatic system, PMLSM, speed and force controller, the load fluctuation and impact resistance characteristics were studied. The result showed that the pneumoelectric force control system could effectively eliminate the influence of the oscillation characteristic of pneumatic system. Compared to the pneumatic control system, the maximum force fluctuation amplitude was reduced from 138N (about 46% steady state value) to 25N (about 8.4% steady state value) under vibration load below 35 Hz; the number of cylinder piston rod oscillation and contact force impact was significantly reduced, and the adjustment time was only 32.3% and 27.3% respectively. The quality of robotic grinding and polishing in shipbuilding industry can be improved by the pneumoelectric robotic end-effector with improved load fluctuation and impact resistance characteristics.