Lo sviluppo del sistema prototipo di Aerospace Shell
Based on the previous theoretical research, and for the process design requirements of typical shell parts of spacecraft, in order to achieve the extraction of the manufacturing features of the parts, the feature extraction tool is designed based on the Siemens NX10.0 secondary development API. Based on the Matlab system software, the process decision rule mining tool and the process route intelligent planning tool are designed. The former realizes the mining function of the potential decision rules of the process data and the machining method decision of the target part, and the latter realizes the process route planning of the target part.
At present, the aerospace shell parts manufacturing unit has a very complete equipment foundation, including 5 vertical CNC lathes, 4 vertical machining centers, 4 horizontal boring and milling machining centers, 2 CNC grinders, and 3 automatic laser guides AGV, 1 set of digital information collection system, etc. On this basis, to face the “multi-type, small-batch” production mode and realize the rapid design of the part process, there are still the following problems:
- (1) The spacecraft shell parts have a large number of processing features and similar geometric shapes, and the feature extraction method based on feature recognition takes a long time to calculate, and it is easy to misjudge the processing features with similar geometric shapes.
- (2) The spacecraft shell parts have high requirements for the reliability of the process route. During the design process, the process personnel need to refer to a large number of historical process documents and review them repeatedly, which severely restricts the efficiency of process design.
- (3) The spacecraft shell parts have a large number of processing features and are constrained by complex process rules, and the manual process route planning is inefficient.
In view of the above problems, analyze the main requirements of the system:
- (1) Spacecraft shell parts include more than 10 typical features such as shape, inner shape, and circular window. The typical processing features are clearly classified and have a high reuse rate, which constitute the main structure of most parts. Facing the typical features of spacecraft shell parts, the feature extraction is achieved through feature parameterized modeling, which can effectively ensure the efficiency and correctness of feature extraction. Therefore, based on the Siemens NX10.0 secondary development API, a feature extraction tool based on parametric modeling is designed to convert the process information contained in the part 3D model into a structured feature element matrix.
- (2) Workshop process data has been accumulated to a certain extent. It is possible to design process decision rule mining tools for the typical characteristics of spacecraft shell parts, mining process decision rules contained in process data, and use process decision rule extraction tools to The target feature matches the appropriate processing method.
- (3) Using structured part features as input, develop process route planning tools to realize rapid planning of process routes. According to system requirements, system development is carried out for the process of parts from 3D model to process route. First of all, a three-dimensional model of the part is established based on parametric modeling, and the processing feature parameter information and the processing feature relationship information contained in the three-dimensional model information of the part are converted into a structured model through a feature extraction tool. Secondly, the process decision rule mining tool is used to mine the process method decision rules in the historical process data, and output the decision rule library. The part structured model uses the process decision rule extraction tool to extract the corresponding processing method from the decision rule library. Technicians allocate manufacturing resources for processing features to form a three-dimensional process step matrix. On the other hand, according to the process feature relationship information and process step relationship information, the process step trend map is organized, and the process route planning is carried out through the process route planning tool.