Study On Signal Processing And Vibration Control Of MSMA Self-sensing Actuator

Magnetically controlled shape memory alloy(MSMA)is a new type of functional material,which has the advantages of large output strain,fast response and high energy conversion rate.MSMA can obtain large magnetic induced strain under the action of magnetic field,this phenomenon is called magnetic controlled shape memory characteristic.At the same time,this characteristic is reversible,MSMA can cause the change of surrounding magnetic field when it is forced to deform,and output the induced voltage signal through conversion.Based on the reversibility of MSMA,a new type of self-sensing actuator is developed,and its signal processing and vibration control are studied.The main work is as follows:The characteristics of MSMA are analyzed,and the mechanical-electromagnetic bidirectional energy conversion working characteristics of MSMA self-sensing actuator are studied,as well as the active vibration elimination principle of the device.Through the theoretical analysis of the mathematical model of MSMA self-sensing actuator's sensing process and execution process,the mathematical model of self-sensing execution process is obtained.Based on the reversible characteristics of MSMA,a self-sensing actuator is developed.Firstly,the equivalent magnetic circuit method is used to analyze the device and study the characteristics of its magnetic circuit model.Then,Ansoft Maxwell,a finite element analysis software,was used to simulate the structure of the MSMA self-sensing actuator to verify the rationality and accuracy of the design.Build the MSMA self-sensing actuator experimental platform.TMS320F28335 DSP is used as the core processor of the experimental system.According to the characteristics of the experimental device signals,the signal processing and control circuit are designed,and the software of the experimental system is designed,so that the MSMA self-sensing actuator experimental system can achieve the expected functions.An adaptive filter based on the least mean square(LMS)algorithm is used to process the sensing signal output by the MSMA self-sensing actuator,which can effectively filter out the interference noise in the signal.Combined with the idea of time-division control,the time slots of sensing,execution and discharge are reasonably configured to solve the problem of coupling between sensing signal and control signal.The MSMA self-sensing actuator is applied to the vibration control system.The experimental results show that the device can play a good real-time vibration damping effect on the periodic vibration force.