A Research on Mechanism Design Optimization
|關鍵字:||動力效應;最佳化;有限元素分析;跨階電動輪椅;dynamic;optimization;FEA;step climbing power wheelchair|
This research focuses on the mechanical design optimization of power wheelchair for step climbing. The transient dynamic effect was concerned by integrating multi-physics theories: the kinematics, dynamics, material strength etc. to solve for the optimal design on the mechanism component especially on the case of impact situation. It is not easy to control and measure the small scale experiment model of proposed PWC wheelchair. Since that the dynamic effect of the PWC system is serious and obvious. Thus, the structural design can not consider maximum static force only, therefore, the design issue of structure need involving dynamic effect that acting on mechanism components. The analysis and simulation stage in our design process are cooperated by two main topics. They are motion analysis involving pre-modeled component mesh and structure dynamics analyzed by adopting the FEA method. For motion analysis of power wheelchair climbing the step obstacle, MSC/ADAMS was introduced to simulate the inertia force and moment exiting at components located at connectors etc. Finite element analysis software ANSYS was adopted to analyze the distribution of the stress that acting on the structure. This analysis was to improve or strengthen the structure in accordance with the material strength. State on the other hand, this research aims to find out the maximum structure stress of wheelchair among dynamic motion by integrating the analysis methods of mechanism motion and structure stress analysis method. Minimum weight as the design object, utilize size optimization to calculate out the best size of geometry and design an optimum mechanism model. The current research proposed a methodology by integrating the kinematics, dynamic analysis and FEA method, have been implemented to demonstrate its efficiency and correctness.