Design And Research Of Automatic Deburring System Based On The Industrial Robot

Industrial robot is a kind of high precision programmable system.Its unique versatilities make it more and more widely used in the manufacturing industry.In the field of deburring,due to the bad working environment,high labor cost and higher product quality requirements,robots instead of manual deburring tasks have become the development trend of manufacturing enterprises.The shortcomings of the traditional online teaching programming cycle and low teaching precision are also gradually appearing,affecting the production efficiency.When the metal parts are deburring,burrs and parts failure is easy to occur when rigid tools are burr removed due to burr hardness,workpiece location errors and robot errors.Especially for large and discontinuous burrs removal.By using the off-line programming technology,the JOB files of tool rail generated form the CAD model can be introduced into the Motoman MH24 industrial robot and the production efficiency can be improved.The flexible deburring actuator is designed to realize the flexible contact between the tool and the part,so as to avoid the breakage of the tool or part due to the error and other factors.In this paper,plastic and metal parts deburring were studied respectively,according to the study on plastic parts deburring,using a car hood trim strip as the research object,the automatic deburring system was designed,and trajectory planning was carried out for deburring processing;aiming at the burr removal of metal parts,the main difference between metal deburring and plastic deburring was analyzed.A deburring flexible actuator was designed and analyzed.The deburring test of the deburring flexible actuator was carried out based on the aluminum alloy wheel hub.The main research contents and conclusions are as follows:(1)The model-flow analysis was used to analyze the springback of the hood trim strip,and the specific fixture was designed by the model after the rebound,and the type of the cylinder was determined.Compared and analyzed the material of the deburring tool,and designed the tool structure with protective function.Completed the design of the peripheral and floor of the automatic deburring system,and the air road structure and electrical were designed according to the process flow of the parts.(2)Researched on the related techniques for the path planning of the burr in the hood trim strip.The D-H model of Motoman MH24 was built,and the forward kinematics equation of MH24 industrial robot was derived by D-H representation.The inverse kinematics of MH24 industrial robot was solved by analytical method,in order to solve the multi solution problem of inverse kinematics,a combination of the best solution which is closest to the front angle was proposed to get the combination of the inverse solution.In path planning,the corresponding interpolation according to the curvature variation of burr edge parts,can be as follows: choose the interpolation of zero curvature sections with linear interpolation,no change in curvature using a section of space circular arc interpolation and changing curvature sections with multi section arc interpolation.The program control points of the small arc section should be reduced the control precision.In the process of hood trim strip deburring,the motion of the robot's joints is smooth.(3)The error source of the off-line program was analyzed and the compensation was made.Through the experiment of deburring,the influence of the cutting angle and the processing speed of robot on the burr quality of the hood trim strip was obtained.The results shown that the suitable processing angle of deburring is 70 degrees,too small can lead to poor processing quality or even no burr removal effect,too large is easy to lead to tool instability.The processing time of the burr is inverse proportional to the robot processing speed,and the suitable robot processing speed for the deburring process is 300mm/s.When the speed is too small,the sawtooth is easy to appear,and the high speed has no obvious improvement on the quality of burr.(4)According to the characteristics and requirements of metal parts deburring,a flexible actuator with multi direction floating was designed.An electric spindle is made up of a EM3030-T-J motor with a large output torque,a spindle and a gear reducer,The structural design of the flexible actuator consists of a radial pneumatic floating ring with a piston,a special joint bearing,and an axial piston structure.The dynamic characteristics of the flexible actuator were studied,and a test platform was built to test the floating threshold,The deburring test was carried out to test the flexible actuator.The results shown that when the speed is 20000r/min,the working speed and the first order natural frequency is close,it's easy to cause the resonance.At different azimuth angles,the radial floating threshold of the electric spindle is different,when the pressure is 0.3MPa,the maximum and minimum radial floating threshold is 48.83 N and 40.92 N,axial float required to overcome the axial floating gravity and friction force of the whole,the floating threshold is larger,when the pressure is 0.2MPa,axial floating threshold is 217.56 N.The designed flexible actuator can finish the deburring of the aluminum alloy wheel hub.