Research On Disassembly Sequence Planning For Complex Product

Disassembly is an important part of a green manufacturing system, which provides an effective approach for resource conservation, environment protection and sustainable development of manufacturing. Design for Disassembly and Recycling (DFD&R) has become a global hot issue and disassembly planning is an effective way to achieve DFD&R. Disassembly sequence planning (DSP) is a key technique for disassembly planning, and the quality of which exerts considerable compacts on the efficiency and cost of product recycle and remanufacture. More specially, the time and cost of the product disassembly can be reduced and the work efficiency can be improved by an optimal disassembly sequence. With the increasing of product complexity, the product disassembly planning efficiency has been seriously affected by the traditional handmade DSP method. Thus, how to realize disassembly sequence planning automatically has become a research focus. In this paper, the disassembly modeling, disassembly sequence planning and disassembly simulation technology are studied, and the feasibility of the proposed methods are also verified.To overcome the disadvantages of the methods for automatic generation of disassembly interference matrix, a method that combines the bounding-box and stepping detection for interference detection based on feature sample points was proposed. By using which, the disassembly matrix (DM) is generated rapidly and accurately, and the computational complexity is also reduced. The process of automatic acquisition interference matrix was given in detail. The part contact relationship and assembly constraint were acquired for building the connection-constraint matrix. The reconstruction methods of these matrixes for the sub-assembly were given. A case was used for analyzed the efficiency of the proposed method.A method of disassembly sequence planning base on ant colony algorithm was proposed. To ensure the geometry feasibility and continuity of the disassembly part, the disassembly information was utilized. The derivation method of disassembly feasibility was given. Based on the improved basic ant colony algorithm, the optimal disassembly sequence was acquired. The system of maximum and minimum ants was used to avoid the local convergence and the performance of algorithm optimization was improved. The detailed steps of the algorithm were given. Finally, a case was used to verify the effectiveness of the proposed method.The multi-objective optimization problem in DSP was analyzed, a multi-objective ant colony algorithm based on Pareto set was proposed, and the construction process of disassembly sequences was presented. The optimal sequence concerning with minimizing the changes of disassembly direction, total disassembly distance and the sequence length was given. The niche was utilized to control the size of the solution set and ensured the diversity of solution set. The optimal selective disassembly sequence was acquired. A case was conducted to demonstrate the feasibly and efficiency of the proposed method.A method of automatic acquiring exploded view was proposed. The disassembly sequence was utilized as data base for the explosion view. The calculation method of exploded distance and construction process of exploded view were presented. The connection matrix was utilized to compute the continuity of exploded. The methods of generating the global and local exploded views were given respectively. Finally, comparison with the automatic exploded view function provided by UG NX, a reducer3D model case study proved the validity and feasibility of the proposed method.Finally, a prototype system for product disassembly planning is developed, where disassembly modeling, disassembly sequence planning and disassembly simulating et al are conducted automatically. A reducer was used as a case to demonstrate the system. Comparing with the similar functions of several existing CAD software, the developed system is demonstrated to verify the effectiveness of the research.