Research On Robotic Abrasive Belt Grinding With Passive Compliance Technology

Blades in aero engines and gas turbines are the key parts involved in energy conversion.They have complex curved surface features,and uneven thickness leads to inconsistent rigidity,which makes it difficult to guarantee machining quality.The blades need to be polished after casting,forging and machining to improve the surface finish and geometric accuracy.At present,the robot sand-belt grinding has shown a good advantage in the blade processing,and the whole grinding system needs to have better stability when grinding combined with the robot's multi-degree-of-freedom flexibility.Therefore,on the basis of the study on the stability of the grinding system,this paper proposes a measurement and control scheme to realize passive compliance,and carries out verification and analysis.The main research work of this paper is as follows:The stability of robot abrasive belt was studied and the measurement and control system was built.The vibration model of blade and sand belt was established by analyzing the contact force in the process of grinding and polishing,and the vibration differential equation was established.Based on the analysis of different vibration forms in the process of grinding and throwing,a dynamic passive submissive solution is proposed,and then a measurement and control system is built.A passive submissive mechanism was designed for the solution,and the actual output force of the cylinder was calibrated experimentally.The closed-loop control of electric proportional valve is adopted to improve the precision and ensure the stable output.By obtaining the feedback value of the measurement,the scheme can dynamically adjust the grinding and throwing machine to meet the requirements of flexibility grinding and polishing.dynamic flexibility based on empirical wavelet transform.Wavelet de-noising is carried out on the measured signals and empirical wavelet transform is adopted.The validity of decomposition is verified by simulation.The energy values of the obtained signals of different frequency bands are calculated and the permutation entropy is extracted,which can effectively identify the instability degree of different vibration forms.application research of measurement and control system software and passive compliance technology in robot belt grinding.On the basis of the research,Labview is used to realize the software and the simulation results verify the noise reduction effect of wavelet and verify the permutation entropy of different components to effectively distinguish vibration forms and accurately estimate their energy.Through comparative experiments,it is verified that the passive compliance scheme proposed in this paper can reduce the oversetting amount by 50% in the grinding and throwing process of the robot belt,and the application effect is verified to ensure that the fluctuation of force in the grinding process is stable within the range of [-1,+1]N.