压电致动微夹钳夹爪位置控制系统设计大学学位论文.doc

压电致动微夹钳夹爪位置控制系统设计 学 生：XXX 学 号：XXX 指导教师：XXX 助理指导教师：XXX 专 业：测控技术与仪器 二O一零年六月  Design on the position control system of a piezoelectrically driven monolithic microgripper Undergraduate: Du Shushuai Supervisor: Prof. Wang Dai Hua Assistant Supervisor: Dong Haomin Major: Measuring and Control Technology Instruments The College of Optoelectronic Engineering June 2010摘 要 微装配机器人在微零件装配、微机电系统(MEMS)、精密光学等领域有着广泛的应用前景。而微夹钳作为微装配机器人的末端执行器，直接决定机器人的工作效果。由于压电陶瓷具有结构紧凑、分辨率高、响应快、无摩擦等优点，故由压电元器件驱动的微夹钳比较普遍。而压电陶瓷自身的迟滞引起的非线性，增加了控制微夹钳的困难。本章提出并研究了前馈补偿和PI反馈控制利用模型前馈补偿控制补偿压电陶瓷执行器的迟滞，通过PI反馈控制实现对的闭环控制，以弥补模型误差和不可测量的干扰。 本文的主要研究工作和成果包括： ①针对理论上难以建立微夹钳位移模型，通过实验的测试，得出压电陶瓷执行器的驱动电压与微夹钳夹持臂的输出位移间的关系，再通过最小二乘辨识或者MATLAB的系统辨识功能来建立位移模型。最后对位移传感器进行位移标定。 ②为实现微夹钳夹持臂位移的控制，本文设计了包括惠斯通电桥、应变信号处理电路、dSPACE和主机四大部分的微夹钳控制系统，完成了包括放大、滤波、零偏校正电路组成应变信号处理电路的设计。通过实验评估，结果表明应变信号处理电路具有较好的性能。 ③针对压电执行器的迟滞现象，本文提出并研究了带前馈控制环节和PID的闭环反馈控制系统，利用得到的传递函数在MATLAB中采用Ziegler-Nichols法仿真得到PI控制器的参数，简化了参数整定过程。 ABSTRACT Microassembly robot is demanding in various fields, such as micro-parts assembly, MEMS(Micro Electro Mechanical Systems)and precise optical projects. As the end-effector of microassembly robot, Microgripper directly determine the effectiveness of robots. As the piezoelectric ceramic actuator has a compact structure, high resolution, fast response, non-friction, etc., the microgripper with piezoelectric actuation are common. The piezoelectric ceramic actuators present the strong hysteresis non-linear relationship between output displacement and driving voltage, which lets the control for the piezoelectric ceramic actuators be difficult. In this dissertation, aiming at this difficulty, the closed loop feedback control system with feed-forward compensation and PID feedback is proposed and studied for microgripper which make compensation for the strong hysteresis relationship between output displacement and driving voltage by the feed-forward compensation and realize the closed loop feedback cont