基于相空间三维动态稳定域的重型车辆稳定性控制策略研究

Study on Stability Control Strategy of Heavy Vehicles Based on Phase Space Three-Dimensional Dynamic Stability Domain

重型商用车存在转动惯量大、控制响应慢等特点。针对重型商用车,基于质心侧偏角、横摆角速度、垂向载荷转移系数设计了三维相空间分析方法,从而判断车辆的实时稳定状态。针对不同的车辆行驶状态,采用AFS控制和AFS/DYC分级控制,并基于利用附着系数设计了可拓控制方法,从而补偿前轮转角和横摆力矩的控制输出,以保证控制器在不同工况下的鲁棒性。通过TruckSim/Simulink联合仿真和硬件在环实验验证了该方法的有效性,并在仿真中通过B-ψ^(·)-LTR判断和B-ψ^(·)判断对比证明了相空间动态稳定域的优越性。仿真和实验结果表明:相比单纯以驾驶员意图操纵车辆,所设计的基于可拓H_(∞)的AFS/DYC分级控制策略可以保证车辆在不同工况下的稳定性,尤其在低附着路面上表现出更好的稳定性,可有效降低车辆在极端工况下发生交通事故的概率。

Heavy-duty vehicles have the characteristics of large moment of inertia and slow control response.For heavy-duty commercial vehicles,a three-dimensional phase space analysis method is designed based on the sideslip angle,yaw rate and vertical load transfer coefficient to judge the real-time stability state of vehicles.For different vehicle driving conditions,AFS control and AFS/DYC hierarchical control are adopted,and the extension control method is designed based on adhesion coefficient to compensate the control output of front wheel angle and yaw moment,so as to ensure the robustness of the controller under different working conditions.The validity of the proposed method is verified by TruckSim/Simulink co-simulation and hardware in the loop experiment,with the su⁃periority of the dynamic stability domain in phase space demonstrated in the simulation by the comparison ofβ-ψ^(·)-LTR judgment andβ-ψ^(·)judgment.The simulation and experimental results show that compared with the way toop⁃erate the vehicle only according to the driver’s intention,the designed AFS/DYC control strategy based on Extension H_(∞)method can ensure better stability of the vehicle under different working conditions,especially on the low adhesion road,and thus effectively reduce the probability of traffic accidents under extreme working conditions.