Research On Key Technologies Of Integrated Joint Module Drive Control System

Robot joint is the core component of robot,and its performance directly affects the overall robot performance.The integrated joint module integrates the parts of frameless torque motor,harmonic reducer,brake,sensor and driver into one,which reflects the design concept of lightweight,modularization and integration,and is an important development trend of robot joints at present.In order to improve the servo control performance of a new integrated joint module,the embedded drive control system is designed and developed in this paper.Focusing on the key technologies of integrated joint module drive control system,the main research contents and conclusions of this paper are as follows:(1)Integrated design of integrated joint module.The functional characteristics and performance indexes of the integrated joint module are analyzed,and the system composition and integrated design method are defined.According to the analysis of the design indexes,the frameless torque motor is determined as the power source of the joint module,and the harmonic reducer is the decelerating device.The selection and design of key components are completed.Finally,the structure design is carried out and the experimental prototype is built.(2)The mathematical model and vector control of frameless torque motor are established.It is difficult to control the mathematical model in the three-phase static coordinate system.The mathematical model in the α-β and d-q coordinate systems is established by using the coordinate transformation method.On this basis,the magnetic field oriented control theory is studied and the principle and technical realization of SVPWM are analyzed in detail.The simulation model of coordinate transformation and SVPWM modulation is built in Matlab/Simulink,and the correctness of the mathematical model and SVPWM modulation process is verified.(3)Control system design and simulation.The joint servo system was built based on the three-loop control structure of current loop,speed loop and position loop,and the relevant control parameters were analyzed step by step according to the control model of each loop.A fuzzy adaptive PI controller with feedforward was designed for the position control of joint modules requiring fast response,high precision,high stability and anti-interference ability.The simulation model of the three-loop control system is built in Matlab/Simulink and the simulation experiment is carried out to verify the effectiveness of the designed servo control system.(4)Hardware and software construction and experiment of drive control system.According to the control requirements of the joint module,the hardware system was built,the hardware schematic and PCB were designed,and the control software was designed on the basis of the hardware system.In order to verify the actual performance of the joint module,an experimental platform was built and prototype experiments were carried out respectively under no-load and loading conditions.The experimental results show that the designed integrated joint module conforms to the design index and has excellent overall performance.