Abstract
In our previous study, we focused on a vehicle suspension as a promising application target of a compliant mechanism and proposed a design method for a vehicle suspension based on a compliant mechanism, or a compliant suspension. In order to design a compliant suspension that satisfies design requirements of a practical vehicle suspension, such as stroke length, camber angle, roll center height and lateral rigidity, our two-stage design method that consists of topology and shape optimization was expanded. In the 1st stage or topology optimization stage, an objective function is modified to evaluate lateral rigidity, which enables to generate an initial concept of a compliant mechanism having high flexibility in a vertical direction, which is a main function of a vehicle suspension, and high rigidity in a lateral direction. In the 2nd stage or shape optimization stage, suspension stroke and camber angle are handled as objective functions, whereas stress constraint, roll center height and lateral rigidity are handled as constraint functions, which yields optimal shape of a compliant suspension. In this paper, we now focus on vibration characteristics of a compliant suspension because the main functions of a vehicle suspension are improving ride quality and running stability by absorbing vibration from road surface while running and vibration characteristics of a vehicle suspension greatly influences ride quality and running stability. Therefore, in this paper, we desgined a compliant suspension using the proposed method and analyize its vibration characteristics.
