Optimization Synthesis of Hybrid Six-Bar Mechanism with Non-Circular Gear Constraints

Abstract

This study proposes an optimization synthesis method of a hybrid six-bar mechanism with non-circular gear constraints for rigid body guidance tasks with complex multi-pose. An innovative evaluation index of the non-circular gear pitch curve is proposed to optimize its non-circularity and smoothness. The first step is the multiobjective constrained optimization of the pose error and non-circular gear pitch curves to obtain the required diversified Pareto front. Secondly, the excellent solution is selected to construct the optimization function of the non-circular gear pitch curve, and the pitch curves of the non-circular gears are further optimized. Finally, a multi-pose transplanting mechanism for vegetable pot seedlings is synthesized using the proposed method. Results show that the optimization effect of non-circularity and smoothness of the non-circular gear pitch curves is evident, and errors between actual and required poses of the hybrid mechanism are minor. The effectiveness of the mechanism is verified via kinematic simulation.

Keywords: hybrid six-bar mechanism, non-circular gear pitch curve, non-circularity, smoothness, rigid body guidance, optimization synthesis.