Abstract: Active steering improves vehicle yaw stability by correcting the front-wheel steering angle. However, existing methods rely on state errors such as yaw rate and sideslip angle to calculate the additional front-wheel steering angle, lacking consideration of the degree of tire force saturation and the available lateral force boundary. This can easily lead to insufficient steering correction or excessive intervention, thereby degrading vehicle handling and stability under large-curvature steering conditions. Therefore, an active steering control method based on tire lateral stability margin is proposed. First, the remaining stability margin is calculated from the front-wheel sideslip angle, and the degree of understeer is constructed to quantify the degree of vehicle instability. Second, the front-wheel correction steering angle is calculated according to the degree of instability, so that the tires are maintained within the range of efficient lateral force utilization. Third, the front-wheel steering angle is constrained according to the vehicle state to avoid excessive additional correction steering angle causing excessive steering intervention, thereby improving vehicle handling stability. Finally, comparisons are conducted with the no-correction control under mild and aggressive circular driving conditions. After applying the correction, under mild conditions, the yaw rate increases by 7% and the front-wheel sideslip angle decreases by 30%; under aggressive conditions, the variation range of the yaw rate decreases by 20%, the peak value decreases by 53%, and the peak front-wheel sideslip angle decreases by 40%, indicating that the control strategy keeps the front wheels away from the sideslip saturation region, optimizes lateral force distribution, and improves handling stability.

Key words: active steering control; tire lateral stability margin; understeer; handling stability

摘要： 主动转向通过修正前轮转角改善车辆横摆稳定性，但现有方法依赖横摆角速度、质心 侧偏角等状态误差计算附加前轮转角，缺乏对轮胎力饱和程度与可用横向力边界的考虑，易 导致转向修正不足或过度干预，进而降低了车辆在大转弯工况下的操稳性能。因此，提出一 种基于轮胎侧向稳定裕度的主动转向控制方法。首先，根据前轮侧偏角计算剩余稳定裕度， 构建不足转向程度用于量化车辆失稳程度。其次，根据失稳程度计算前轮修正转角，使轮胎 维持在侧向力高效利用区间。再次，根据车辆状态对前轮转角进行约束，避免附加修正转角 过大导致转向过度干预，提高车辆操纵稳定性。最后，在平缓与剧烈绕圆工况下，与无修正 控制进行对比。采用修正后，平缓工况下横摆角速度提高 7%、前轮侧偏角降低 30%；剧烈工 况下横摆角速度变化范围降低 20%，峰值降低 53%，前轮侧偏角峰值降低 40%，表明控制策 略使前轮远离侧偏饱和区、优化了侧向力分配并提升操纵稳定性。

关键词: 主动转向控制；轮胎侧向稳定裕度；不足转向；操纵稳定性