压电陶瓷微夹钳迟滞环自适应逆控制研究

Study on Adaptive Inverse Control of Hysteresis in Piezoelectric Microgripper

针对压电陶瓷的迟滞特性可使微夹钳难以获得良好的位移控制的问题,提出自适应逆控制策略。推导了压电悬臂位移特性的理论模型;采用自适应最小均方算法滤波器建立了压电悬臂的基于Backlash算子的迟滞环正逆模型,并以此为基础建立了微夹钳位移的自适应逆控制系统。样机测试和跟踪实验结果验证了所建立的理论模型和迟滞环模型的正确性,以及控制系统良好的自学习能力和控制效果。

A control strategy of adaptive inverse control was presented for the problem that the hysteretie characteristics of piezoelectric cantilever made the microgripper difficult to get a precise displacement control. First, the theoretic displacement model of piezoelectric cantilever was established. Then, this paper established the hysteretic model and its inverse model based on Backlash operator by introduced the adaptive LMS filter. An adaptive inverse displacement control system was constructed based on models for the microgripper. The results of testing and tracking experiments show that the theoretic model and the hysteretie model are correct, and the control system has good characteristics of self learning and control actions.