Development of a Generalized Mathematical Model for Slider-Crank Mechanism Based on Multiobjective Concurrent Engineering with Application

Abstract

A design optimization of a slider-crank mechanism (SCM) based upon multiobjective concurrent engineering is presented in this paper. The proposed generalized mathematical model includes geometric equations, kinetic–dynamic expressions, fatigue strength and stability requirements and allows to take into consideration the manufacturing capabilities available. The model also allows for describing the actual mechanism characteristics and can be used directly for the detailed design stage of SCMs, in contrast to the simplified physical models available for preliminary design. Based on this approach, the multiobjective model of SCM which includes 11 variables, seven constrained expressions and the three most important objective functions (total mass, required power and maximum dynamic reaction) was developed. The closed-form analytical expressions were established to the relationship between objective functions, constraints and variables. The correctness of the model was checked by using the finite element method. By using the developed model, the optimization design of the main transmission of a fruit/vegetable washer was carried out. The genetic algorithm optimization has yielded 73 Pareto optimal solutions, and the three most suitable solutions according to the specific manufacturing capability were determined by employing a decision-making process based on the method of successive concessions. Further, a comparative study showed that the solutions obtained by the developed model have excelled the one obtained by means of the experience-based approach. It is noteworthy that the generalized mathematical model and the problem-solving approach adopted in this work can also be used for the SCM synthesis of other mechanical systems.