Research On Piezoelectric Six-dimensional Force Sensor With Small Size And Large Range And High Precision

As a kind of sensor which senses all information of six-dimensional force and moment in space,six-dimensional force sensor plays an important role in force position control of monitoring link,and is widely used in intelligent medical,aerospace,intelligent factory and other fields.With the opening of the era of Intelligent Manufacturing Based on the Internet of things,intelligent equipment has put forward new requirements for sensor measurement technology,such as multi load real-time measurement under complex working conditions,structure miniaturization and lightweight,and precise control of high-precision feedback.The widely used resistive and piezoelectric six axis force sensors have many limitations,such as large size and complex decoupling,which have become one of the main factors restricting the development of intelligent equipment.Therefore,the basic testing theory of piezoelectric six-dimensional force sensor with small size,large range and high precision is studied.In this paper,based on the piezoelectric effect and the area division method,an integrated six-dimensional piezoelectric force measurement principle is proposed.Based on the theory of mechanics and piezoelectricity,the force and potential distribution of the area element of quartz wafer under six-dimensional force are analyzed,and the mapping expression between the area charge and vector force is deduced.The feasibility of the measurement principle is verified by the finite element software.In this paper,the effect of different chip positions on the measurement results in the multi-layer quartz wafer measurement scheme is studied,and the reasonable layout of the force sensing elements is finally determined.On the basis of the integrated measurement principle,a single point support sensor structure is designed.The load transfer process is analyzed and the static and dynamic analytical model is established.The theoretical calculation formulas of charge sensitivity and natural frequency are derived.The influence of the parameters of the force sensor on the sensitivity and natural frequency is analyzed.Based on the genetic algorithm,the sensor structure is miniaturized and optimized,the genetic optimization model is established,and the optimal parameters of the sensor are finally determined by using the multi factor constraints of the finite element software.After static simulation and modal analysis,the optimized sensor's EMF and mode shape are obtained,and the sensitivity and natural frequency are calculated.In order to solve the problem of serious coupling error of sensors,the six-dimensional force nonlinear decoupling algorithm is studied.Based on BP neural network and PSO particle swarm optimization algorithm and GA genetic algorithm,the decoupling effect of sensors is analyzed.