形状记忆合金(shape memory alloy,SMA)是一类新型功能材料,作为电热驱动器,广泛应用于工程领域。但由于材料内在的非线性性质和迟滞效应使其在控制系统的设计和热力学建模上较为困难,不利于简单控制系统和实时控制的实现。基于Preisach理论给出SMA驱动器系统的温度-位移迟滞模型,分析系统的热传导过程,将传统的比例-积分-微分PID(proportional-integral-differential,PID)策略应用于控制器的设计,并引入蚁群和粒子群两类智能算法优化控制器参数,讨论优化过程和控制效果;与传统PID参数整定方法相比,系统的阶跃响应和正弦信号跟踪性能取得比较理想的效果,且智能算法调节控制器参数的实时性更强,克服非线性和迟滞效应的影响。
Shape memory alloy is a new functional materials,which was popular with many applications in various fields as a result of good candidate to be excellent electrothermal actuator.However,the inherent nonlinearity and hysteresis occered in material that pose a challenge in the design of control system and thermomechanical modeling that was of significant importance in implementing a simple controller strategy and realtime control.In this paper,a hysteretic model relating the displacement to the temperature of SMA wire based on preisach theory was presented,the fundamentals on the thermal transfer in actuator is explored,and then the traditional proportional-integral-differential control was idealed to this nonlineaer system with the optimizing parameters by the huristic algorithm like swarm particle and ant colony strategy.Compared to the conventional method regulating the PID parameters,the intelligent algorithms optimizing the controllers can track the step signal and sinsoidal input better,and was stronger in real time,overcoming the nonlinearity and hysteresis in the actuator system.