面向软性磨粒流加工的流速模糊控制

Flow velocity fuzzy control about softness abrasive flow machining

针对软性磨粒流加工过程中因粘度变化导致工件表面加工质量不均匀的问题,提出了一种通过实时的调节流速来提高表面加工均匀度的方法。针对软性磨粒流加工流速调控的复杂性以及高度非线性的特点,设计了一套面向软性磨粒流加工的模糊控制系统,利用模糊控制不需要知道控制对象的精确数学模型的特点,较好地实现了对软性磨粒流流速的控制,达到了传统的控制方式所无法实现的控制目的;根据软性磨粒流的加工特点和加工经验,设计了合理的隶属度函数和模糊控制规则,从而使模糊控制器的设计更为合理;利用Matlab软件中的模糊逻辑工具箱和Simulink模块对模糊控制器和模糊控制系统进行了仿真。仿真结果表明,模糊控制可以很好地实现对软性磨粒流加工流速的调速,并且能获得较为满意的控制精度。

Aiming at the question that the process of softness abrasive flow machining can result in the uneven machining surface and machining quality, because of the change of viscosity, a method that through adjusting the flow velocity to improve the evenness of machining surface was put forward. Aiming at the feature about the complexity of regulation and control of softness abrasive flow velocity and altitudinal nonlinearity, a set of fuzzy control system was designed. As the fuzzy control need not to know an accurate mathematical model of the object, the control of the flow velocity of softness abrasive flow could be realized well, which can＇t be achieved by the traditional method of control. According to the machining features and machining experience of softness abrasive flow, a design project for reasonable membership function and control rule was put forward, which makes the design of a fuzzy controller more reasonable. The fuzzy controller and the fuzzy control system were simulated by using the fuzzy logic toolbox and simulation modules in Matlab. The results indicate that fuzzy control can adjust the flow velocity of softness abrasive flow well, and can get more satisfactory control accuracy.