Development And Application Of Six-dimensional Force Sensor Based On MRE

The six-dimensional force sensor is the most comprehensive type of sensor for measuring force information.It can measure the constantly changing force/torque information in the spatial range.Because the measured force/torque information is relatively complete,it has been widely used in the world.However,the existing six-dimensional force sensors have some problems at different levels,such as: 1)The sensing unit of the six-dimensional force sensor has not been reformed,and most strain gauges are used as sensing units,but the strain gauges have deformation limits and are easily damaged.The problem is that the sensitivity is low under a large range of conditions;2)Strain gauge patch technology is still used,and long-term service will cause the performance of the strain gauge to deteriorate and the adhesive layer to fall off;3)The beam structure with elastic deformation beam type is still used,with large load It may cause plastic deformation,resulting in sensor failure;4)A six-dimensional force sensor with a self-decoupling structure is not easy to package;5)The reliability of the body and sensitive unit is relatively low,and the sensor life will be reduced;6)The operation of sleeve preloading preloading is difficult,and the preloading effect cannot meet the requirements.Aiming at the problems existing in the existing six-dimensional force sensor,this paper developed a built-in stepped six-dimensional force sensor.The new MRE material with silicon rubber as the matrix replaces the strain gauge as a sensitive unit to improve the life of the sensing element;Replacing the fixing method of the sensitive unit with pre-compression to solve the problem of failure of the sensitive unit under long-term service;replacing the elastically deformable beam with a rigid beam reduces the risk of plastic deformation of the elastically deformable beam;replacing the cross beam type with a new embedded stepped structure The traditional structure reduces the difficulty of operation during preloading,improves the accuracy during preloading,enhances reliability,and realizes structural decoupling.On this basis,the preparation process was optimized for the MRE sensitive unit,which was most suitable for the verification of the ratio,and based on the series-parallel-parallel resistance model,the piezoresistive sensing model was derived;further,the new design Based on the embedded stepped structure,a six-dimensional force sensing model is established.Based on the USB-6210 data acquisition card from National Instruments,the corresponding voltage signal acquisition program is designed,and the threshold denoising algorithm based on wavelet transform is used to denoise the six-dimensional force signal;the experiment proves that: after wavelet denoising The signal is good,its standard deviation change rate is 1.8537,and the fluctuation range is 0.3mv,which can be used as a six-dimensional force sensor signal denoising algorithm for practical application.A nonlinear decoupling algorithm based on ant colony algorithm optimized BP neural network is used to realize the software decoupling operation of the six-dimensional force sensor,and a new six-dimensional force sensor calibration device is designed to fully calibrate the six-dimensional force sensor.Finally,according to the results of actual test sensitivity and linearity,the sensor has good sensitivity and linearity,which can meet the requirements.On this basis,the six-dimensional force sensor is applied to the field of grinding and polishing,which realizes one-time optimization of the grinding trajectory and real-time constant force grinding.The actual grinding and polishing situation is analyzed to meet the requirements of grinding and polishing.