利用轮速信号和防抱死制动系统(ABS)控制器提供的压力调节状态确定ABS减压过程的最大滑移率和轮速回升阶段的最大车轮角加速度,提出了一种基于这两个特征参数的路面附着识别算法。通过实车ABS道路试验,获得不同路面附着条件下这两个特征参数在坐标平面内的分布,并根据特征参数点在该平面内的分布规律确定能够区分高、低附着路面的分界线。为防止误判,根据由参考车速确定的制动减速度对识别得到的路面附着进行修正。采用不同附着路面条件下的ABS制动试验实测数据对算法进行验证,结果表明在仅测量轮速的情况下可有效识别高、低附着路面。
A new algorithm for mad adhesion identification by using the maximum slip ratio during ABS pressure release and the maximum wheel angular acceleration during wheel speed restoration is proposed. These two parameters are determined by using wheel speeds and pressure regulation states from the ABS controller. Distribution of the characteristic parameters in the coordinate plane under different road adhesion conditions is analyzed by using ABS road test data. A boundary between high mad adhesion and low mad adhesion is found according to the distribution. The identified road adhesion is further modified according to the vehicle deceleration estimated using the reference vehicle speeds to avoid misidentification. ABS brake test data under various road adhesion conditions are used to evaluate the algorithm and results show that the algorithm can effectively identify high and low road adhesion conditions by measuring wheel speeds only.