基于加速度反馈的平面3-■柔性并联机器人自激振动控制

Self-excited Vibration Control of the Planar 3-■ Flexible Parallel Manipulator Based on Acceleration Feedback

平面3-RRR柔性并联机器人在精密定位、物料搬运、宏微结合等领域有着广泛应用,其在运行到某些区域时容易产生自激振动,这极大地影响了系统的精度和稳定性。为了有效抑制并联机器人的自激振动,在并联机器人试验平台上搭建了振动加速度测量系统,利用加速度传感器和伺服电动机实现闭环反馈以及自激振动主动控制。对平面3-RRR柔性并联机器人特定奇异位置自激振动的机理进行分析,考虑加速度信号滤波以及信号传输和处理等因素引起的相位滞后,采用移相技术,给出了基于加速度反馈的控制算法,对平面3-RRR柔性并联机器人的自激振动进行了主动控制试验研究。理论和试验结果表明:提出的基于加速度反馈的主动控制方法能够在奇异位置处有效抑制并联机器人的自激振动。

Planar 3-RRR flexible parallel manipulator is widely used in the precision positioning, material handling, macro-micro combination and other fields. It is easy to generate self-excited vibration when running to some areas, which greatly affects the accuracy and stability of the system. In order to effectively suppress the self-excited vibration of parallel manipulator, the measurement system of the vibration acceleration is built on the parallel manipulator experimental platform, and the closed-loop feedback and self-excited vibration active control are achieved by acceleration sensor and servo motor. The mechanism of the specific singular position of the planar 3-RRR flexible parallel manipulator is analyzed. Considering the phase lag caused by the filtering and the transmission and processing of the acceleration signal, the technique of the phase shifting is adopted and the control algorithm based on acceleration feedback is given. The active control experimental research of the self-excited vibration of planar 3- RRR flexible parallel manipulator is developed. The theoretical and experimental results show that the proposed active control method based on acceleration feedback can effectively suppress the self-excited vibration of parallel robots at singular positions.