Design Of Microforce Sensor Based On IPMC

Ion-exchange Polymer-Metal Composites (IPMC) is an intelligent electrical deformable material, which has light weight, good flexibility and can be cut into arbitrary size and shape. When IPMC is exerted low voltage, a comparatively big displacement can be generated. Most importantly, when exert displacement the material can generate faint voltage. So, the study of IPMC has great value to Microforce control and biomedical applications.This paper systematically introduces the cantilever beam sensor theory. Using PCI6221data acquisition card and LabVIEW, the IPMC’s sensor characteristic is systematically studied, and IPMC differential amplifying circuit and filtering circuit are designed and debugged on that basis.Firstly, this paper introduces the relationship between the IPMC’s sensor voltage based on LabVIEW system and water content, and then deduces the force-deformation model, and uses MATLAB to fit the model to get IPMC force-deformation model. By analysis of the relationship between deformation and sensor voltage, the transfer equation of the force is obtained. To increase the accuracy and reduce the error, the relative theory and design method of FIR filter are expounded.Secondly, a whole set of sensor lab platform is designed. Because the detected force signal is very small, the hardware, which includes pre-amplifier (differential amplifier) and its filter circuit, is designed. Chose TMS320F2812as the processing unit to minimize the Microforce sensor and guarantee its accuracy. The circuit includes power source circuit, reset circuit and LCD display circuit etc. To increase the accuracy of AD conversion, AD976A is applied. And the anti-interference circuit is designed, and the corresponding hardware is debugged.Thirdly, use CCS to design the software program, which includes DSP initialization module, watchdog module, AD module, and LCD display module etc. Expound the design process.At last, use LabVIEW system to demarcate force sensors and determine its parameter.