Research On The Compliance Control System Of The Robot With Torque Sensorless For The Grinding And Polishing Of Flexible Bodies

As smart manufacturing advances,the application of industrial robots in the manufacturing industry has boomed.Products' grinding and polishing is one of the important links in the field of product manufacturing,albeit with problems including that the uniformity of grinding and polishing cannot be guaranteed,and the cost of employment is high.The upgrading of the traditional manual grinding and polishing process technology promotes the wide use of robot technology in this field,most of which treats the grinding and polishing of rigid workpieces as objects and some industrial products are not rigid but have flexible properties,where as the direct use of the grinding and polishing technology to develop robot rigidity cannot meet the quality requirements.Under such circumstances,studying the polishing characteristics of flexible body and designing torque sensorless controllers for robot polishing technology has not only paramount theoretical guidance significance but also enormous practical meaning.Unlike rigid workpieces,flexible bodies will deform after being stressed,and meanwhile its position,posture,and polishing force would change with different points of action.As such,how to track the position,posture and polishing force of the deformed surface is the difficulty of the robot control system design in the process of polishing the flexible body.To this end,this study selected the traditional cowhide grinding and polishing process as the research object.By consulting the relevant literature and its own properties,a virtual experiment platform was constructed using ABAQUS finite element analysis software to simulate and extracted the position,posture,and grinding and polishing force of the cowhide surface after deformation.Meanwhile,based on this series of parameters,guided by the principles and methods of 6R robot compliance control,a set of control system technical solutions was constructed,and a simulation virtual platform was built through the Matlab 2019 b.It also conducted in-depth research and simulation on key technologies such as deformation trajectory tracking and impedance control,with a view to providing technical support for the future design of hardware and software for flexible body torqueless robot grinding and polishing controllers.The main contents are as follows:First,the status of robot grinding and polishing technology at home and abroad is analyzed,and the main research route in the research process of this article is introduced.Then,taking the Kawasaki RS010 N robot body as the research object,the D-H method was used to establish the kinematics model and extrapolate the inverse kinematics solution.At the same time,the robot dynamics was analyzed using Newton's Euler method,and the robot kinematics and dynamics model building and model verification are completed in the Matlab 2019 b software.Afterwards,the pose track input of the control system was studied.Due to the fact that during the process of grinding and polishing the flexible body,there will be the problem that the flexible force deformation will cause the grinding and polishing tool head to fail to track the trajectory correctly.The paper used ABAQUS finite element analysis software to build a virtual experiment platform,simulated and extracted the position,posture and polishing force process parameters after the deformation of the cowhide surface.Through the deformation trajectory parameters and the use of Frenet frame,the position was planned and the posture and trajectory after the deformation was used as the trajectory input of the control system.Then,the design of the force and position control system in the process of robot grinding and polishing was carried out.Using decomposition acceleration control as the robot position strategy and impedance control as the force control strategy,the control system was built and simulated and verified in the Simulink integrated environment.After that,the robot joint motor control system and torque sensorless technology were studied.Taking DC motor as the research object and fuzzy PID control as the robot joint motor controller,an algorithm is developed,and a robot single joint motor control system is built.The key to the realization of robot force control is the collection of terminal force feedback.In the research process,this paper used torque sensorless technology to collect the force of the robot end tool to reduce the cost of the robot flexible body grinding and polishing task.Finally,it enumerated the research results and innovations of the full text,meanwhile pointing out the shortcomings in the process and put forward prospects for the future.