Research On Service Robot Joint Integrated Torque Sensor

With the rapid advancement of robotics,the application environment is showing increasingly stringent requirements for robotic drive systems and their control capabilities.While having rigid driving capability,it also requires the robot limb to exhibit proper flexibility in the process of contact with the outside world.In the integration of the control system,the driving system should also have the ability to sense the magnitude of the torque it receives.The robot thus designed can share the same workspace with humans without causing accidental harm to humans.In the process of frequent interaction with people,the robot must also demonstrate the same ability to handle tasks as the creature.Therefore,in this process,the robot's ability to perceive the information of its own joints is crucial.Based on the planar torsion spring designed and developed by the laboratory,an integrated torque sensor for the knee joint of the robot was proposed,and the optical principle was used to sense the torque information of the single degree of freedom at the knee joint.The following research work was carried out mainly for this sensor:1.The development status of the current robotic compliant drive is outlined,and the development of the multi-dimensional force sensor and its key technologies are introduced in detail.The design of the torque sensor with the optical sensing principle used in this paper is obtained.2.Starting from the simulation analysis combined with the mathematical method,the mathematical regression equation of the elastic body(planar torsion spring)is obtained by the finite element analysis of the three-dimensional model combined with the response surface methodology,and then further optimized by the minimum value of the elastic strain matrix condition number.It is suitable for the elastomer solution used in the design of the torque sensor,while avoiding the significant impact on the mechanical performance of the compliant drive.3.The response surface methodology is described in detail in this paper.This is a kind of design of the plane torsion spring structure parameters by the center composite test,so that all the variable values are at the test center point,and then the elastic body is fitted by the model evaluation standard and the response surface analysis software.The response value analytical method communicates the relationship between the structural parameters of the elastomer and the strain values.4.According to the detection principle adopted,the experimental analysis shows that the temperature has a great influence on its output,and then the BP neural network with hybrid particle swarm optimization algorithm is used for temperature compensation.Finally,based on the designed circuit,the analysis software is used for simulation,and the results are in line with the design expectations.The plane torsion spring will inevitably have inter-dimensional coupling interference in the actual environment.These interference forces are error combinations for the detected objects.Therefore,the least square method based on the coupling error is used for calibration decoupling.