基于非奇异快速终端滑模的非线性轮胎力控制研究

Studyon tyre friction control based on non-singular fast terminal sliding mode

针对分层式集成控制系统在不同路面工况下车辆纵向力的控制问题,提出了一种基于模型的实时估计方法.首先选取魔术公式作为参考轮胎模型,并采用有约束混合遗传算法对其关键参数进行实时优化辨识,从而可以计算得到不同路面工况下与目标控制力对应的目标控制滑移率.采用非奇异快速终端滑摸控制方法(Nonsing ular Fast Terminal Sliding Mode,NFTSM)设计纵向滑移率控制器(Longitudingl Slip ratio Control,LSC)对目标滑移率进行跟踪控制.仿真结果表明:所提出的轮胎-地面力控制策略可以很好地跟踪不同路面工况下的滑移率,满足上层控制所需的目标控制力,从而对车辆进行优化控制.

Based on the longitudinal tyre friction control, the relevant coefficient via the magic formula and key parameters under different road surfaces are identified on-line through the proposed constrained hybrid genetic algorithm （GA）. For a specific tyre friction, the corresponding control objective of slip ratio is first obtained using a numerical method. Then, a nonsingular fast terminal sliding mode （NFTSM） control method is employed to track the desired slip ratio, i.e. longitudinal slip ratio control （LSRC）. Evidently, such serial algorithms as parameter evaluation, optimization and control are adapted to the variation of road surfaces. Finally, it is concluded from simulation experiments that the tyre friction can be tracked precisely and rapidly to meet the adaptation requirement upon road surface variation.