Research On Continuous Collision Detection Method Based On Open CASCADE Platform

To solve the non-assembly problems caused by design errors,assembly path or assembly sequence in products' actual assembly process will have a huge cost,virtual assembly can verify the products' assembling ability due to assembly simulation,and it will improve the products' development efficiency and competitiveness.The core of products' assembling ability verification is collision detection algorithm,most of existing collision detection algorithms are non-continuous or static algorithms,which can't satisfy the double requirement of virtual assembly system for the accuracy and real-time,and a small number of continuous collision detection algorithms only can be applied to some specific background.Therefore,the goal of this thesis was to design a set of collision detection method that can meet the needs of development of complex mechanical products.This thesis designed a set of continuous collision detection method that applied in VAS virtual assembly platform according to the existing problems of collision detection,and the main work and achievements are as follows.This thesis designed a collision detection method based on projection,which can ensure the accuracy of the algorithm and transform the 3D collision detection problems into 2D,and this method reduced the difficulty of implementing algorithm to improve the efficiency of collision detection.Interpolation method was designed to improve the projection precision of BSpline curve based on irregularity of mechanical model,this kind of strategy improved the completeness and efficiency of collision detection method.A fast filter method was designed for' batch modules' collision detection,which made the collision detection stepped into assembly object collision detection method quickly.In the method of assembling object collision detection,the Euler-Gagnon quadratic curve intersection algorithm was designed to improve the efficiency of large-scale quadratic curve intersection,and the efficiency of the whole collision detection method was improved globally.And the sub-algorithms had high real-time and accuracy by experiments and analyses,the whole method was verified in theory,the results showed that the method had high completeness and integrality and can be used theoretical support and data source for the method's integration.This thesis proposed a set of collision detection method of theoretical,which included filtering of collision-free objects method and assembly object collision detection method.This method has high real-time and accuracy by analyzing and the set of methods can meet the requirement of virtual assembly system for developing complex mechanical products.