Design And Research Of Structural Decoupling Force/Torque Sensor Based On Reconfiguration Strategy

This paper presents a sensor model of force and torque which have achieved structure decoupling by its elastic body structure.The related theory,finite element simulation and experimental study are carried out.The six-axis force sensor has been studied from the aspects of configuration synthesis,decoupling condition,optimization analysis,statics analysis,reconfigurable modeling,sensor prototype design and the test calibration.Compared to assembly type structure decoupling six axis force sensor,it has hignly accuracy,and the model of reconstruction is simple.It provides the theoretical basis and design basis for the structural decoupling force / torque sensor in the static performance and the specific application of model reconstruction.Firstly,by using the method of screw theory to analysis the structure of the sensor we discover the six-axis force sensor is decoupling,and the validity of the structure is verified by the analysis of the decoupling constraints.The structural dimension of the beam is determined by orthogonal test.According to the size of the beam and the linear cutting process,the structure design and the optimization design of elastic body is completed.Finally,we determine the structure of the sensor at the end of the completion,elastic body shell and bottom plate design work according to the structure,and finally determine the bridge method of sensor bridge,completed the overall design of the sensor.Secondly,the changing of the output strain curve in the finite element software is studied under the condition of different load and torque.The coupling condition of the sensor is analyzed and the coupling phenomenon is analyzed from different aspects.According to the relationship between the external load and strain,the isotropy of sensitivity and stiffness is analyzed,the stiffness model of the sensor is obtained.By using the response surface methodology to analyze the influence of sensor structure parameters on sensor sensitivity.The six-axis force sensor's sensitivity are used as the optimization objective,and the optimal solution of sensor structural parameters is obtained.The finite element method is used to calibrate the sensor,virtual calibration matrix and error matrix are obtained,which provides a theoretical basis for the design of the sensor.Then the reconfigurable strategy of structure decoupling six-axis force sensor is analyzed,and the comparative analysis of the reconfigurable model between the indirect output sensor and the direct output sensor is conducted.The reconfigurable structure measurement principle of the decoupling structure sensor is given.By means of virtual calibration method,the calibration matrix and error matrix of the decoupling force / torque sensor are presented.In the case of the calibration matrix,the programming of the software reconstruction algorithm is completed,and realizing the adaptive reconstruction ability of six axis force sensor for measuring the specific task.At last,according to the calibration experiment platform,the experimental research on the reconfigurable calibration of the sensor is carried out.Based on the analysis of calibration experiment,the important static performance parameters of the sensor are calculated,which reflects the good performance of decoupling force / torque sensor.