Design And Research On Pro/E-Based Cable Harness Assembly Planning System

Cable harness is a kind of important component in electro-mechanical system which carries electric currents and electronic signals, and it is widely used in electro-mechanical products such as weapon equipments, aircraft, cars and personal computers. Cable routing is very complicated and has an important influence on the quality of electro-mechanical products. At present, mock-up is used to verify the rationality and correctness of the cable harness assembly in engineering which exists problems including long development terms and high production costs. Meanwhile the attached pictures of cable harness assembly in the process cards are usually two-dimensional. It is very difficult to instruct the assembly workers effectively for these abstract drawings. With the development of virtual assembly technology, a new platform is provided to solve these issues, which is important and positive for reducing cabling repeat rate and improving the quality and productivity of electro-mechanical products.Based on the requirement of some defense enterprise, cable harness assembly planning system based on Pro/E is designed and developed with the goal of practical application. The main work is as follows.1. Cable harness 3D geometrical model and assembly objects information model are founded. It is put forward that the center curve of cable harness is described by the cubic B-spline curve through the given points and the cable harness 3D geometrical model is built by the method of curve scanning. Based on that, the assembly objects information model is built which consists of rigid assembly information model, electrical assembly information model and cable harness information model. A new way is presented to express cable harness by using base cables and branch cables.2. The key technologies of the cable harness assembly interactive planning system are studied. Based on the "hierarchical assembly model" and "disassembly priority constraint matrix", the assembly sequences of the products including the rigid parts and the flexible parts are planned by the man-machine interactive way. The rapid interference detection algorithm composed of the qualitative check and quantitative calculation is proposed. Two methods to make animation are researched. The method is that the animation for rigid-flexible assembly is created by the functions from Pro/TOOLKIT. And the other method is that the animation for cable harness routing process is created by the method of intercepting screen.3. Based on the Pro/E platform, the prototype system is developed by using Pro/TOOLKIT, database of Oracle and the integrated development environment of VC++.