Research On Assembly Technology Of Automobile Alternator Frame In Multi-station Machining Based On Force Sense

In the multi-station processing of automobile alternator frame,the gripping and placing technology of the frame is the key technology for assembling robots on the automated production line.However,the traditional assembly robot must be taught point by point to complete the "pick-place" action.The picking point,the placing point and the locus of the pick-place are all determined beforehand,so the automation production line must be highly structured.Especially,the workpieces on conveyor belt are moving and scattered,and the positions and postures of picking and placing points are generally not fixed,which greatly limits the application of traditional robots in modern flexible production lines.The force sensing is introduced into the multi-station processing assembly of the automobile alternator frame,which can adapt to complicated processing conditions,and does not need to adjust the precise position of each fixture again according to the characteristics of the product.To this end,this paper puts forward the research of "research on assembly technology of automobile alternator frame in multi-station machining based on force sense ",which will greatly improve the adaptability of robot processingFirstly,the multi-station processing technology of the automobile alternator frame is analyzed,and a multi-station processing assembly platform of automobile alternator frame is built according to the process characteristics.The selection of the specific type and parameters of the six-dimensional force sensor is analyzed,and the hardware structure of the six-dimensional force sensor is expoundedThe alternator frame and fixture assembly problem as a whole is simplified to a dual peg-in-hole assembly problem.All possible one-point contact states and two-point contact states during the assembly process are proposed(L-1)～(R-10).The contact force analysis is carried out on the typical one-contact state L-1 and the typical two-point contact state L-5,and the relationship between the corresponding assembly forces Fx,Fy,Fz and the assembly moments Mx,My,Mz is obtained.According to the relationship between these assembly forces and assembly moments,the corresponding jamming diagrams are obtained.The validity of the analysis is verified by the experimental platform built in the earlier stageThe corresponding control strategy of the assembly is studied.Firstly,the fuzzy force control lemma of the automobile alternator frame assembly is proposed and proved in X-O-Y,Y-O-Z and X-O-Z planes respectively.Then the principle of impedance control algorithm is introduced.Finally,different assembly strategies are proposed according to different stages of assemblyThe experiment of multi-station machining of automobile alternator frame robot based on actual production line is carried out.Robot assembly system is built Threshold calibration of different positions and postures in the free assembly stage of alternator frame is completed.The assembly experiment of automobile alternator frame is successfully carried out.The maximum assembly force and the maximum assembly moment are 159N and 13.5N·m in the assembly process.The experimental results verify the correctness and validity of the previous analysis.