Integrated Robot Joint Design And Impedance Control Research

Compared with traditional robots,collaborative robots have certain advantages in intelligence,ease of use,safety and rapid layout,especially for flexible manufacturing.the Integrated joint design and impedance control of collaborative robots are the key factors to ensure its light weight and safety.At the same time,impedance control is the key technology for the application of collaborative robots in axle hole assembly and connector assembly.In the light of the above problems,this paper focuses on the mechanism,sensor and control of the integrated joint of collaborative robots,and proposes the impedance control method of collaborative robots to improve the light weight and safety of collaborative robots and realize flexible control.Firstly,the background of collaborative robots and integrated joints is analyzed in this paper.On this basis,an integrated joint with joint driver,encoder,motor,reducer and torque sensor is proposed.A realization method of absolute magnetoelectronic encoder is proposed.A structure of torque sensor suitable for robot joints is proposed.The finite element model of the sensor is established.The statics characteristic and linearity of the torque sensor are analyzed.The signal processing circuit of the torque sensor is designed.The hardware principle of the servo driver for joints is proposed and the prototype of the driver is designed.Secondly,the principle and coding method of magnetoelectronic encoder based on pseudo-random sequence are proposed.The decoding principle and subdivision principle of magnetoelectronic encoder are analyzed.The software program of decoder is designed,including the main program of decoder,pseudo-random decoding program and subdivision program module.In the aspect of joint driver,the principle of direct drive motor vector control is analyzed and the software architecture suitable for joint driver is proposed,including driver main program,A/D interrupt program module and vector control module.Then,the overall configuration and control scheme of the manipulator of the collaborative robots are analyzed.Establish the control system model of joint space;identify the parameters of joint and link,including weight,gravity center,friction and other parameters;propose the impedance control method of joint space;establish the impedance control model based on MATLAB/Simulink,and test the impedance control algorithm by simulation.The control model of the manipulator in Cartesian space is established,and the impedance control algorithm in Cartesian space is designed and simulated.Finally,verifing the feasibility of the integrated joint design based on torque sensor and the impedance control algorithm of collaborative robot through simulation and experiments.