Multiobjective Optimization of Steering Mechanism for Rotary Steering System Using Modified NSGA-II and Fuzzy Set Theory

Abstract

Due to the complicated design process of gear train, optimization is a significant approach to improve design efficiency. However, the design of gear train is a complex multiobjective optimization with mixed continuous-discrete variables under numerous nonlinear constraints, and conventional optimization algorithms are not suitable to deal with such optimization problems. In this paper, based on the established dynamic model of steering mechanism for rotary steering system, the key component of which is a planetary gear set with teeth number difference, the optimization problem of steering mechanism is formulated to achieve minimum dynamic responses and outer diameter by optimizing structural parameters under geometric, kinematic, and strength constraints. An optimization procedure based on modified NSGA-II by incorporating dynamic crowding distance strategies and fuzzy set theory is applied to the multiobjective optimization. For comparative purpose, NSGA-II is also employed to obtain Pareto optimal set, and dynamic responses of original and optimized designs are compared. The results show the optimized design has better dynamic responses with minimum outer diameter and the response decay decreases faster. The optimization procedure is feasible to the design of gear train, and this study can provide guidance for designer at the preliminary design phase of mechanical structures with gear train.

Vibration control analysis of vehicle steering system based on combination of finite-element analysis and modal testing

“…Zhao et al (2018) established a steering structural parameter optimization model for an electric-hydraulic hybrid steering system and proposed a hybrid particle swarm optimization algorithm to realize global information exchange. Li et al (2015) minimized the dynamic vibration response of the steering mechanism by optimizing the structural parameters under geometric, kinematic, and strength constraints. However, the wide vibration frequency range of the vibration source makes it easy to produce unstable resonance vibration when coupled with the frequency of some of the components of the steering system; thus, parameter adjustment is required to produce a characteristic change.…”

“…(2018) established a steering structural parameter optimization model for an electric–hydraulic hybrid steering system and proposed a hybrid particle swarm optimization algorithm to realize global information exchange. Li et al. (2015) minimized the dynamic vibration response of the steering mechanism by optimizing the structural parameters under geometric, kinematic, and strength constraints.…”

Multi-objective optimization design of cycloid pin gear planetary reducer

“…It was shown that NSGA-II obtained better optimization objective values than other methods. Li et al 17 combined NSGA-II and fuzzy set theory to optimize dynamic model of steering mechanism and got the better result than the original design. However, far too little attention has been paid to the research about multi-objective optimal design of cycloid speed reducers.…”

A New Methodology for Solving Trajectory Planning and Dynamic Load-Carrying Capacity of a Robot Manipulator

“…The NSGA-II algorithm was originally proposed by Deb et al [36]. It has been proved to be a highly effective and generally successful choice for optimization problems and becomes one of the mainstream solutions to multiobjective optimization questions [37][38][39].…”