Research On Pro/E-Based Three-Dimensional Computer-Aided Assembly Process Planning System

Three-dimensional CAD softwares have found their wide application in the manufacturing industry. But Three-Dimensional Computer-Aided Assembly Process Planning(3D-CAAPP) systems based on three-dimensional CAD softwares are now only in the preliminary stage of development and applicatioin. Traditional two-dimensional CAD-based CAAPP can't meet the requirement of CAD/CAAPP integration and the visualization of process planning, thus obstructing the IT deployment in these corporations.Considering the above-mentioned flawness regarding the two-dimensional CAD-based CAAPP, a new 3D-CAAPP system based on Pro/E is proposed in this thesis. Also the techniques of process planning and on-the-spot instructing by animation clips are introduced, in order to help process planners to interactively make related process files. The main work is illustrated in the following aspects:1. The assembly information model targetting specifically the three dimensional computer-aided process planning system is introduced, with the integration of geometrical information and process-specific information, providing the information source for the following assembly process planning.2. The key techniques including assembly sequence plan, path plan, assembly process animation are studied in this thesis: the"three-step"sequence planning method is put forward, containing hierarchical planner, geometrical planner and computer-human interactive planner; the postion-orientation matrix is used in assembly path planning; the animation is created by the functions from Pro/Toolkit, a software redevelopment package supplied by PTC.3. The prototype system is developed by using Pro/Toolit and MFC, with Pro/Engineer as the operating platform. The modified hierarchy of assembly information model is demonstrated. Through establishing some key points and their position-and-orientation matrixes, assembly path planning and interference checking are carried forward. The process planning related information and results are stored in ACCESS. Finally the three-dimensional assembly process documents and assembly animation clips are created to instruct in assembly shop.Summarily, the three-dimensional CAAPP prototype system based on Pro/E is developed after studying the systematic structure of the system and its key techniques, shedding light on the"Assembly Line Visualizaition"and CAD/CAAPP integration in the three-dimensional CAD platform.