| Variation design is widely used in the field of engineering design.In the variation design of two-dimensional engineering drawing,the existing CAD software has not yet realized the automatic adjustment of dimension line,surface roughness,shape and position tolerance and other marking symbols in the view,which needs to be adjusted manually.Manual adjustment is not only a heavy workload,but also error-prone.Therefore,enterprises urgently need the adaptive adjustment of two-dimensional engineering drawing labeling information for variant design.According to the actual engineering needs,this paper studies the key technologies such as rapid adjustment of 2D engineering drawing annotation information associated with 3D model variation design.It mainly studies the automatic recognition and extraction method of 2D engineering drawing annotation information,and the adaptive adjustment method of annotation information position.In this paper,an adaptive annotation information adjustment method for the variation design of two-dimensional engineering drawings is proposed,and a prototype annotation and annotation system is developed.The main research contents are as follows:1.To solve the problem of complex and repeated setup of 2D engineering drawing templates,parameterized CAD software was used to establish parameterized 2D engineering drawing templates according to drawing standards.And from the drawing format,view rendering,layer setting,title bar setting and extraction of material list and other aspects of expansion,can effectively solve the engineering drawing and template setting complex problems.2.The labeling information in some two-dimensional engineering drawings is not consistent with the existing standards.In this paper,a method of batch modification of old GB marking symbols is proposed.The old GB marking forms of surface roughness objects and reference objects are automatically recognized,and their marking information is extracted and then marked again.3.In the variation design of two-dimensional engineering drawing,the size of the view of the two-dimensional engineering drawing will change.In order to ensure the quality of the drawing,it is necessary to automatically adjust the dimension line,surface roughness,shape and position tolerance and other marking information accordingly.In this paper,an adaptive adjustment method of multi-objective engineering drawing annotation information is proposed,and an adaptive adjustment system of 2D engineering drawing annotation information is developed to realize the adaptive adjustment of 2D engineering drawing with one key.Meanwhile,the versatility of the method is verified.4.In an enterprise type 430 friction clutch,for example,has developed 430 type friction clutch cover assembly digital system design,the development of the system integrates 3 d model parametric design and adjustment function in two-dimensional engineering graphics elements,implements the 430 type friction clutch cover assembly 3 d model parametric variant and quickly generate two-dimensional engineering graphics,to verify the practicability of the proposed method. |
