| At present,for the polishing of metal materials such as aluminum parts and steel parts,the processing methods are still widely used manually.Workers rely mainly on experience for production,resulting in poor quality of polishing and processing.Robotic force control polishing provides a new way to solve this problem.The force control actuator can not only solve the force coupling problem in the polishing,but also can regulate various process parameters in the polishing.In the robot polishing,several parameters that have a great influence on the polishing process are the rotational speed,the feed speed and the polishing tool force.According to the characteristics of the parameters in the polishing process,the design,analysis and preliminary experimental research on the force control actuator and its control system in the robot polishing are carried out.According to the requirements of the polishing process,this paper proposes the design goal of the robot force-controlled polishing end effector.In order to meet the design goals,the principle of increasing the response bandwidth and reducing the overturning moment is adopted in the design process.According to the design principle of force-controlled polishing actuator,the design of actuator is divided into three levels of function,behavior and structure by axiomatic design method.Then,based on the virtual design technology,the structural design of the robotic force-control end effector was carried out.Finally,the reliability of the force control actuator design is verified by finite element analysis.In order to design the control system of the robotic polishing actuator,the basic framework of the force control system is constructed according to the basic principle of servo control.The hardware structure of the control system is designed and implemented through technology such as motor and drive power matching,amplifier circuit and communication.Based on the MATLAB scripting language,the variables of the control software are designed and the main program of the control software is determined.In this paper,the electromechanical system of the robotic force control end effector is modeled,and the frequency domain,time domain and stability of the electromechanical system are analyzed.Based on the principles of low-pass filtering,voice coil motor and digital PID,the active force control algorithm of the actuator is established according to the signal relationship of the electronic circuit of the control system.In order to verify the feasibility of the algorithm,the main dynamic control algorithm was simulated and analyzed by SIMULINK toolkit.In order to verify the polishing effect of the robotic force control actuator in the actual polishing operation,the prototype of the actuator was first developed and the experimental platform was built.The zero drift and proportional drift of the force sensor were calibrated using experimental methods.On this basis,the force control performance of the actuator was tested,and the force control performance under dynamic operation was further tested.Finally,the process parameters were planned and conducted an experiment. |
