The Research On Multi-functional Composite Integration Of Five Axis NC Machine Tool Error Modeling And Measurement Technology

With the continuous development of modern manufacturing, precise and ultra-precise manufacturing technology plays more and more important role. As the basic manufacturing equipment of the development of new high-tech industry and cutting-edge industry, CNC machine tool is widely used in the production site.Currently research on synthetic error modeling and measurement technology of five-axis CNC machine tool is still relatively small, with the support of the national science and technology major project:"high-level machine tool and basic manufacturing equipment",this thesis focuses on five-axis CNC machine tool’s synthetic error modeling, step diagonal measurement of geometric errors, temperature measuring point optimization and modeling of error element and other related content.The main contents of this thesis are as follows:Research on five axis CNC machine tool’s error source analysis and error movement mechanism. This thesis analyzes the five-axis machine tool’s structure and main error sources, identifies machine tool’s shifting and revolute joint’s error elements, and gets the machine tool’s all geometric and thermal error elements eventually. By analyzing the machine tool’s error movement kinematic, the shifting and revolute joint’s error motion equations are founded to lay the foundation for synthetic error modeling.By analysis of five-axis CNC machine tool’s position structure and movement relationship, this thesis gives dual turntable five-axis CNC machine tool’s synthetic error model. The relation between tool and the work piece is descript by a multi-body posture relationship, The relation between tool and the work piece is expressed as the tool to the bed’s "tool-Bed" kinematic chain and the work piece to the bed’s "piece-Bed" kinematic chain. By using the standard homogeneous transformation technology for rigid body, this thesis founds dual turntable five axis CNC machine tool’s synthetic error model, finally gets the CNC machine tool’s synthetic error model by small error assumptions, and verifies the correctness of the model.This thesis researches on fast step diagonal measurement technology of the CNC machine tool’s volumetric errors. Five-axis machine tool’s structure is very complex, geometric error elements are too many, although the direct measurement method is highly precise, but the efficiency is relatively low. therefore, this thesis uses step diagonal measurement method for volumetric errors, by step measuring the working space’s four body diagonal errors, combining with the error recognition technology of geometric errors, we can quickly get the machine tool’s nine position errors and three vertical errors.This thesis researches on thermal error measurement system and temperature measuring point distribution optimization technology. In this study, the laboratory develops a temperature and thermal error measurement system, and we measured the temperature and thermal errors’data. Based on Partial correlation analysis, we find the sensitive heat source points, this method can greatly reduce the number of temperature measuring point and achieve the target of thermal error’s temperature measuring point distribution optimization.