拼焊板零件变压边力鲁棒控制策略研究

针对拼焊板零件冲压成形过程中恒压边力方法的不足,提出基于混合H2/H∞理论的变压边力控制方法,建立了变压边力混合H2/H∞控制模型,设计了变压边力混合H2/H∞控制算法和控制逻辑。采用该模型对拼焊板零件冲压成形进行反馈数值模拟,分析有无变压边力混合H2/H∞控制对拼焊板零件成形缺陷的影响,并在变压边力冲压机上进行试验验证。仿真和试验结果表明：基于混合H2/H∞理论的变压边力控制方法可成功冲压出车身前围上盖板,可有效避免恒压边力下的起皱和破裂两种缺陷,该控制方法同时考虑冲压行程和压边板位置进行压边力优化,具有更好的鲁棒性。     

Multi-objective optimization of active steering system with force and displacement coupled control

A novel active steering system with force and displacement coupled control (the novel AFS system) was introduced, which has functions of both the active steering and electric power steering. Based on the model of the novel AFS system and the vehicle three-degree of freedom system, the concept and quantitative formulas of the novel AFS system steering performance were proposed. The steering road feel and steering portability were set as the optimizing targets with the steering stability and steering portability as the constraint conditions. According to the features of constrained optimization of multi-variable function, a multi-variable genetic algorithm for the system parameter optimization was designed. The simulation results show that based on parametric optimization of the multi-objective genetic algorithm, the novel AFS system can improve the steering road feel, steering portability and steering stability, thus the optimization method can provide a theoretical basis for the design and optimization of the novel AFS system.     

力与位移耦合控制的主动转向系统协同优化

设计一种力与位移耦合控制的前轮主动转向(Active front steering,AFS)系统,使其同时具有主动转向和电动助力转向功能,不仅实现汽车转向轻便性和转向路感的完美融合,而且实现汽车安全性与灵活性的协调统一,是一种理想的汽车动力转向技术。建立新型AFS系统和整车3自由度动力学模型,提出新型AFS系统的性能指标及量化公式,应用协同优化方法,考虑人机工程学、汽车安全性和转向经济性三个子系统,以转向路感为系统级优化目标,对新型AFS系统参数进行协同优化设计。仿真结果表明,基于协同优化的新型AFS系统可在保证系统具有较好的转向稳定性、转向灵敏度和转向能耗基础上,有效提高系统的转向路感,为新型AFS系统的设计和优化提供理论基础。