Research On Robot Assembly Technology Based On Trajectory Planning And Force Control

With the proposal of the strategic concept of "made in China 2025",China's robot industry is also booming.Robots have begun to replace manual labor and are widely used in various industries.In the past,robot automation,intelligent degree is not high,mainly used to complete grasping,handling,welding and other simple tasks that only need precise position control,but with the continuous development of society,robot only complete simple tasks,has been unable to meet the needs of social development,we need to apply robot to transportation,grinding,assembly and other intelligent degree more High mission.In this paper,trajectory planning and compliance force control of assembly robot are studied.(1)This paper introduces the robot experimental platform built in this paper,and uses DH method to model the forward kinematics of UR3 robot,uses analytical method to model the inverse kinematics of the robot,and solves the pose of the end of the robot.(2)Aiming at the problem of local optimal value and target unreachable in the artificial potential field method,the improved artificial potential field method is combined with the dynamic motion element method to form the robot motion planning algorithm in this paper,so that the robot can still generate a successful obstacle avoidance trajectory when there are obstacles near the target point.(3)For the compliance control of robot,this paper uses model free adaptive impedance control as the force control algorithm.Firstly,the principle of impedance control is analyzed.Aiming at the uncertainty of environment position information and environment stiffness information in impedance control,model free adaptive control is introduced.Through input and output data,the parameters of mass parameter m(t)and damping parameter b(t)in impedance control are estimated and adjusted online to reduce the tracking error of position and force,Improve the robot assembly accuracy.The simulation experiment is carried out.(4)The template matching method is used as a visual positioning algorithm with the robot,and through the transformation of the coordinate system in the robot space,the positioning attitude of a target object is obtained.In order to ensure the safety and effectiveness of the above test methods,the robot assembly experiment platform is built by ourselves.