Optimum design and analysis of a novel planar eight-bar linkage mechanism

Abstract

Planar mechanisms are essential for many applications. The metal forming process is a vital application for industrial sectors such as automotive and space. Manufacturing precision and generating dwell motion are also important issues. These properties cannot be realized on conventional mechanical presses. Therefore, a novel single degree of freedom (1DOF) eight-bar planar mechanism was developed in this study. The main advantages of the new mechanism are slider balance and dwell motion without a servo motor. Thanks to these advantages, manufacturing difficulty and cost can be reduced. In this study, the new mechanism was modeled kinematically and verified. An optimization methodology was also presented for determining the mechanism dimensions. In order to achieve the desired dwell motion, dimensions of the mechanism for three cases (stroke capacities with 60 mm, 600 mm (crank length ≤ 300 mm), and 600 mm (crank length ≤ 250 mm)) were optimized by using the Genetic Algorithm (GA). The optimized dimensions were also compared kinematically, and the comparison results were shown. The best-optimized dimensions were determined based on the position, velocity, and acceleration simulations of the new mechanism.