Research On Grinding Trajectory Planning Of Casting-cleaning Robot

Castings are metal forming objects obtained by various casting methods,which account for a large proportion of metal forming objects.Due to the inherent defects of casting method,the flash and riser produced in the production process of non-precision castings are irregular and unevenly distributed.As the main contents of cleaning castings,flash grinding and cutting of gating risers are still mostly people’s work,with high labor intensity,dirty,disordered and poor working environment.Not only the production efficiency is low,but also the noise and dust in production do great harm to workers’ health,and accidents occur frequently.Therefore,the research of automatic casting-cleaning robot for non-precision castings has become the most important part of the development of foundry industry.In this thesis,by analyzing the characteristics and cleaning methods of the flash and riser of sand casting,a casting-cleaning robot based on 2D-laser-profiler is proposed.The quadratic curve fitting grinding trajectory planning of orthogonal space curve is proposed.The main contents of this thesis are as follows:(1)By analyzing the causes and characteristics of casting-cleaning characteristics,the key technologies of casting-cleaning robot were summarized.These key technologies include the method of picking up features of casting-cleaning,the way that the robot carries the tool for main motion and feed motion,the scheme of casting-cleaning robot,and the method of initial error calibration.(2)The design of key parts,communication and control system of casting-cleaning robot was completed.According to the layout of the casting-cleaning robot,the equipment used was selected and the communication platform between the devices was established.Laser scanning strategy of cleaning-characteristic was formulated and the control program structure was designed based on the strategy.(3)The grinding trajectory planning of flash and gate riser has been completed.By constructing orthogonal space curve,the contour of the body near the cleaning feature is restored,and the cleaning feature is picked up and analyzed according to the restored contour.Finally,the grinding trajectory is planned according to the fitting strategy of piecewise quadratic curve.(4)By setting up the experimental platform,the position and attitude of the moving target of the robot are controlled by the casting-cleaning-controller instead of the DeviceNet station,which verifies the correctness and effectiveness of the communication platform.Through software simulation,it is verified that the trajectory planning of flash-grinding meets the requirements under two working conditions.This thesis realizes the communication between 2D-laser-profiler,casting-cleaning-controller and robot-controller.The aim of trajectory planning of flash grinding using laser data acquisition is achieved,which provides a technical basis for the further realization of casting-cleaning robot.