Research On Constraint Relation Analysis And Collision Detection In Virtual Assembly Based On CATIA/CAA

Assembly design is an important part in the product design. With virtual reality technology being more and more mature,virtual assembly becomes an important research direction on its applications and also provides a new way for assembly-oriented design and evaluation. Some present main research status are investigated,and the key technologies and the generic flow chart of virtual assembly are concluded .Collision detection is resolved to be virtual assembly's essential technology. Advanced algorithms and technologies of collision detection are synthesized. Combined with CATIA and CAA software characteristics,a new mentality and realization method is developed:(1)The three-dimensional bounding boxes were obtained through CAA,and the collision detection was carried on using it as preliminary judgment,objects that bounding boxes didn't intersected were rejected.(2)The objects that bounding boxes intersected were operated through boolean operation,the collision objects and the collision spots were discovered.(3)The assembly process may be regarded as component space positions transformation , which corresponds to its space transformation matrix, therefore the dynamic collision detection may be considered as a series of static collision detection. The feasibility and validity are confirmed through the example,and collision detection based on CATIA/CAA is implemented successfully.