Research On Error In-Situ Visual Detection And Compensation Principle And Method Of Profile Gdinging

Profile grinding is widely used in the machining of profile curve parts,such as all kinds of precision complex moulds and cutting tools.As a precision machining method of curve parts,how to improve its machining accuracy becomes an important research project.Error compensation is widely used in the researches as an economic and effective method for improving machining accuracy.However,the existing error detection and compensation methods of profile grinding exist some shortages,such as low efficiency,bad compensation effect,etc.At the same time,along with the development of computer technology and image processing technology,computer vision is widely used in the field of machining error detection,which has the advantages of high efficiency,rapid,non-contact.Therefore,this paper did research on the machining error in-situ vision detection and compensation of profile grinding.The main contents and results are as follows:(1)Introduced the principle of profile grinding based on machine vision.Then designed the experimental platform of profile grinding based on machine vision,and emphatically introduced the design of vision system.Common image quality evaluation methods were introduced.Selected the energy gradient method,which sets image clarity as its target,to evaluate the quality of the images got by the selected vision system hardware.At the same time,evaluating the image quality subjectively from the respect of visual effect.The evaluation results showed that the principle of vision system hardware selection was correct.(2)On the basis of profile grinding principle,a new grinding wheel wear detection and compensation method based on local visual image was put forward.The corresponding detection and compensation principle of the proposed method was introduced.Corresponding simulation experiment method was designed according to the characteristics of the profile grinding.Then simulation experiments for the proposed method were carried out.The experiment results showed that the proposed method can detect and compensate the grinding wheel wear effectively.(3)A machining error synthetical detection and compensation method through the combination of machine geometric error compensation with grinding wheel wear error compensation based on local visual image was studied.For the geometric error modeling method,based on the multi-body system kinematics theory,the topological structure and error elements of profile grinding machine were analyzed,and the error transfer law between each component was studied.The geometric error model was finally established.The model was simplified based on the analyzation of error characters,which provided a foundation of the synthesize error compensation for further improving the accuracy of profile grinding.(4)On the basis of the profile grinding principle,a machining error real-time detection principle and compensation method based on global visual image was put forward,and simulation experiments were carried out.The experiment results showed that the proposed error detection and compensation method can detect and compensate error of different size in different directions effectively,which provided a new method to improve the machining accuracy of profile grinding.