Research On PSO Model Identification And Direct Teaching Of Industrial Robot

Industrial robots have become an indispensable means to increase productivity and the advanced robot control technology depends on the accurate dynamic model.The traditional robot dynamics model does not consider the actual situation of the influence of the dynamic characteristic,therefore the dynamic model identification of industrial robot has an important significance to improve the control precision and efficiency.The industrial robot is developing towards light weight,and the human-robot cooperation ability is improving,there appear new requirements for the robot teaching techniques accordingly.Compared with the traditional teaching technique by teaching pendant,the direct teaching technology has the advantages of high efficiency,simple operation,low requirements for the operator,thus it has become the focus of the development of robot teaching technology.Particle swarm optimization(PSO)algorithm is an intelligent optimization algorithm based on population evolution,it has the advantages of easy implementation,high precision,fast convergence,while other intelligent algorithms do not have the advantage in solving practical problems.In this paper,based on the improved PSO algorithm,the identification of the dynamic parameters of the industrial robot is studied.Firstly,based on the PSO theory,an improved PSO algorithm is proposed to identify the dynamic parameters of the robot.In this method,the observation matrix of parameter identification is obtained by improving the Newton Euler dynamics modeling method,and the dynamic parameters are identified by the improved PSO algorithm.The kinematic parameters are identified on the UR industrial robot,and the accuracy and effectiveness of the proposed algorithm are verified according to the torque prediction accuracy..Then,according to the identification of the dynamic model,the control method of force-sensorless direct teaching for the industrial robots is studied.On the basis of force-free control which based on position control,a force-sensorless control method for direct teaching based on joint current is proposed,and this method controls the joint speed directly.The simulation results show that the proposed control method can control the motion of the robot according to the external force,and the robot can be taught directly without additional force sensors.Finally,the experiment of direct teaching and teaching repetition was carried out on UR industrial robot.The specific joint data of UR robot are obtained based on the TCP/IP protocol.The current will be filtered to remove noise interference.Then,the data are processed according to the established dynamic model.The generated script code is sent to the robot to realize the direct teaching of the robot.According to the record of the teaching information,the computer generates teaching documents,and realizes the teaching and playback.The experimental results verify the effectiveness and feasibility of the proposed force-sensorless control method for direct teaching based on joint current.