Sequences planning for products disassembly based on lowest levels disassembly graph method
Résumé
Integration of disassembly operations during product design is an important issue today. As known, the number of possible disassembly sequences increases significantly with the number of parts in a product. Thus, generating proper disassembly sequences is critical. Most of existing methods often require tremendous computational resources while, at the same time, they often fail to find realistic and optimal solutions for complex products disassembly. For selective disassembly, for instance, it is important to eliminate the components which are unrelated with the target prior to sequences’ generation. In order to address this configuration, this paper deals with a method for generating the feasible disassembly sequences for selective disassembly. It is based on the lowest levels of a disassembly product graph. Instead of considering the geometric constraints for each pair of components, the proposed method considers the geometric contact and collision relationships among the components in order to generate the proposed Disassembly Geometry Contacting Graph (DGCG). The generation of the disassembly sequences is based on the investigated three cases called micro unites, which consider all the possible situations of relationships among the components in the DGCG. The latter is then used for disassembly sequence generation thus allowing decreasing the number of possible disassembly sequences. For this purpose, a mixed Virtual Reality Disassembly Environment (VRDE) is developed based on Python programming language using mixed VTK (Visualization Toolkit) and ODE (Open Dynamics Engine) libraries. It is applied for automatic generation of the selective disassembly sequences and is illustrated within two examples.