Evolving planar mechanisms for the conceptual stage of mechanical design.

This study presents a method to evolve planar mechanism prototypes using an evolutionary computing approach. Ultimately, the idea is to provide drafts for designers at the conceptual design stage of mechanism design which meet their design brief. The designers can review, analyze and incorporate the drafts into the development of a mechanical system. This work proposes a stepping stone towards a generative design system which is capable of evolving such planar mechanisms with a focus on the configuration and shape of their components. In this paper, we present a use-case of evolving four-bar linkages with attached shaped component to study the evolutionary approach. In addition to kinematics, we consider properties such as the shape of levers, placement of rotation joints, torque, friction, restitution, and mass. The design aim was to move a mechanism as fast as possible in the forward direction whilst overcoming obstacles in a virtual environment involving gravity. Our method was evaluated using complex environments with different obstacles. The results verify that it was able to evolve a variety of high performing mechanism drafts. The study provides a promising outlook of using this method to support the conceptual stage of mechanical design.