Analysis of Multi-Process Machining Errors of Frame Parts Based on State Space

The critical processing characteristics of components are key in ensuring product accuracy and quality consistency. This paper focuses on the key machining characteristics of frame parts and develops a multi-process machining error prediction model based on the state space theory to anticipate machining errors. Firstly, the error sources such as reference error, fixture error, and machine tool geometric error during the multi-process processing of frame parts are described using the homogeneous coordinate transformation theory, multi-body system theory, and error transformation theory. Secondly, a multi-dimensional model is constructed using the above error sources to predict the machining error process. Lastly, the sensitivity analysis of the multi-process machining error prediction model is performed using partial derivatives to study the contribution of each error source to the multi-process machining error prediction model during the processing of frame parts. The model's effectiveness is verified by taking the machining process of the external surface key machining feature of frame parts as an example, and the contribution of each error source to the errors of the key machining feature of frame parts is further explained.