Optimum synthesis of a four-bar mechanism using the modified bacterial foraging algorithm

This paper presents the mechanical synthesis of a four-bar mechanism, its definition as a constrained optimization problem in presence of one dynamic constraint and its solution with a swarm intelligence algorithm based on the bacteria foraging process. The algorithm is adapted to solve the optimization problem by adding a suitable constraint-handling technique able to incorporate a selection criterion for the two objectives stated by the kinematic analysis of the problem. Moreover, a diversity mechanism, coupled with the attractor operator used by bacteria, is designed to favor the exploration of the search space. Four experiments are designed to validate the proposed model and to test the performance of the algorithm regarding constraint-satisfaction, sub-optimal solutions obtained, performance metrics, and an analysis of the solutions based on the simulation of the four-bar mechanism. The results are compared with those provided by four algorithms found in the specialized literature used to solve mechanical design problems. Based on the simulation analysis, the solutions obtained by the proposed algorithm lead to a more suitable design based on motion generation and operation quality.