Abstract
An optimal shape design system for planar link mechanisms is developed using an object-oriented modeling technique. In the formulation of the shape design problem, the driving forces required for the motion of the follower are considered as objective functions to be minimized, and relationships on kinematics and statics are investigated as constraints. The process of mathematically formulating the problem is so complicated that the usual optimization techniques are not effective enough to support the shape design. In our system, link mechanisms are represented using an object-oriented modeling technique based on their graph representation. Based on the representation, the formulation for optimal design is automatically carried out. The system has effective user-interface functions for setting initial shapes of mechanisms and showing results of optimization calculation. Finally, it is applied to the optimal shape design of a power shovel in order to check its validity and effectiveness.