基于形状记忆合金驱动器的微纳定位系统鲁棒自适应控制

Robust adaptive control for nanopositioning system based on shape-memory alloy actuators

针对基于智能材料驱动器串联驱动的微纳定位系统,本文主要探讨了此类高精定位系统的控制设计策略.其控制设计的主要任务是消除驱动器中未知回滞特性对系统性能所造成的负面影响.本文重点以形状记忆合金驱动器为例,采用基于广义play算子的广义Prandtl-Ishlinskii回滞模型来表征形状记忆合金驱动器中的未知饱和回滞非线性,并在此基础上提出了一种鲁棒自适应控制设计方法来消除前置回滞存在的影响.设计的控制器在保证全局稳定性的基础上能实现理想的跟踪精度,仿真结果验证了控制策略的有效性和正确性.

For nanopositioning system with actuators made from smart material,the control approach for this class of high-precision positioning system is addressed.The crucial point of this task is to mitigate the adverse effects caused by the unknown hysteresis.In an illustrative example,we employ a generalized Prandtl-Ishlinskii model with generalized play operator to describe the unknown saturated hysteresis in the shape-memory alloy actuator,and develop a robust adaptive controller to mitigate the effects of the preceding hysteresis.This controller realizes a precise trajectory tracking,while ensuring the global stability for the closed-loop system.The effectiveness of the proposed control approach is demonstrated through a simulation example.