Research On 3D Photoelectric Torque Sensor With High Integration

With the trend of intelligent development in robot industry,it is necessary to install torque sensors in joints.The torque sensors should be small,lightweight and highly integrate.However,the existing commercial torque sensors are of large size,expensive and difficult to be customized.They are difficult to be applied to joints.Under the background,it is selected that the photoelectric measurement principle with non-contact measurement.And the research of multi-dimensional photoelectric torque sensor with high integration is carried out.At present,photoelectric torque sensor has become the focus of research at home and abroad.And certain results have been achieved.But there are still some areas existing problems.There are fewer dimensions to measure,and most can only be measured in one dimension.Configuration of elastic element is single,and exists the problem of multi-dimensional stiffness mismatch.Multi-dimensional decoupling solution is not mature enough for new measurement system and configuration.Aiming at the shortage of photoelectric torque sensor,the research of three-dimensional photoelectric torque sensor with high integration is carried out.In this paper,the main research carried out in this paper is as follows:Firstly,layout of the multi-measuring units and elastic element are designed.Put forward the multi-measurement units are divided into two groups,the horizontal group and the vertical group,and differential layout.The layout isolates the multi-dimensional measurement,and reduces the coupling among dimensions,At the same,it is improving the anti-noise and reducing the temperature drift.Put forward the solution "turn straight beams into curved" to solve mismatch of stiffness among the dimensions.Through finiting element analysis,the result shows "turn straight beams into curved" can optimize to match stiffness among the dimensions and reduce the maximum stress and improve reliability.Then,the data acquisition and debugging system are designed.The data acquisition board implements required functions,including multi-channel signal acquisition and a variety of communication methods.The upper computer software implements required functions,including data acquisition,data save with the database form,the display of error curves,and the rewriting of the decoupling matrix.On the basis,experiments and decoupling among dimensions are researched.The result is that a scheme which the first data preprocessed based on theory analysis for the layout of multi-measurement units,after solving the decoupling matrix based on the neural network is proved to be effective and feasible.Finally,a test platform is built to test the static characteristics of the three-dimensional photoelectric torque sensor including its linear,sensitivity and so on.By doing a series of experiments,it proves that the torque sensor designed meets the requirements.