Research On Wrist Force/Torque Sensor Based Compliant Control Of Door Opening

At present,the robots are widely applied to industrial,military,aerospace and other automational field.In order to make the robot better to be adapted to the working environment and modify the trajectory of the end of the mechanical arm real-time.This paper researches the method based on the mechanical arm zero calibration of wrist force/torque sensor and completes the mechanical arm compliance control operation which was carried during the open tasks.we selected the six degrees of freedom mechanical arm which was from Schunk company as the research object.Firstly,we have established a control system which the core was setted with Schunk mechanical arm,selected Advantech ARK5260 as the host.Using Gugao GTS series motion controller to control the mobile platform and using MFC to code the man-machine interface to control the mechanical arm and related equipment.And then we researched the basic kinematics analysis of mechanical arm,completed mechanical arm respectively in Cartesian space and joint space planning,implemented the basic motion planning of robotic arm to perform a task.Secondly,we tried to find a solution to the problem of the measuring results of wrist force/torque sensor can be influenced by load end's attitude change when mechanical arm moves by proposing a load gravity compensation algorithm for wrist force/torque sensor.According to gravity variation of the load end in different mechanical arm posture,the relevance between the gravity of load end and the position of the center of gravity can be measured by experiment.We created a wrist force/torque sensor gravity compensation model and from this we deduced a load gravity compensation algorithm for wrist force/torque sensor and a calculation method for force acting on the end of mechanical arm through manipulator kinematics equation.Specific examples have been tested by adopting the ADAMS and MATLABjoint simulation method.The results show that this compensation algorithm can effectively eliminate the influence of the attitude change of load end,the external force information of mechanical arm can be measured by wrist force/torque sensor.And the results verify the correctness of the load gravity compensation algorithm for wrist force/torque sensor.Finally,this paper analyzed the mechanical arm force in the process of open the door combining with position control based on Cartesian space.In order to ensure the mechanical arm can be controled to open the door smoothly.This paper proposed a planning that open the door smoothly based on impedance control,and selected process parameters properly based on the simulation and planning the smooth open operation experiment process,and verified the mechanical arm can realize the high-precision force smooth controlling to open the door.