During braking with ABS (Anti-Lock Brake System), low braking initial speed causes to build-up and reduce brake pressure in longer time period due to extending application time of brake pressure and response time of solenoid valve. Also, the decision about speed and acceleration variations of wheel becomes very difficult due to weak speed signals arising from low speed. This results in lower braking torque than needed on the wheels. Therefore, effects of weak wheel speed signal become more pronounced in critical road conditions due to sudden changes in wheel speed. In this study, the effects of these problems occurring in low speed were investigated on both control and braking performance of ABS under critical road conditions. For this, ABS tests were carried out for low and high speeds on four different road types, which include slippery, wet and µ-jump tests (from wet to slippery and from slippery to wet). In this way, the results were compared to both vehicle speed and road type. The test results show that the low speed worsens braking stability, control and braking performance of ABS, regardless of road conditions. For this reason, it is proposed that ABS control algorithm must be divided in two parts as low and high speed control.

在使用 ABS（防抱死制动系统）制动时，由于制动压力的施加时间和电磁阀的响应时间延长，制动初始速度低导致制动压力积聚并在较长时间内降低。此外，由于低速产生的速度信号较弱，因此很难确定车轮的速度和加速度变化。这导致制动扭矩低于车轮所需的制动扭矩。因此，由于车轮速度的突然变化，在临界路况下，弱车轮速度信号的影响变得更加明显。在这项研究中，研究了这些问题在低速下对临界路况下 ABS 控制和制动性能的影响。为此，在四种不同的道路类型上进行了低速和高速 ABS 测试，包括湿滑、湿和 µ 跳跃测试（从湿到滑和从滑到湿）。通过这种方式，将结果与车辆速度和道路类型进行了比较。测试结果表明，无论路况如何，低速都会恶化 ABS 的制动稳定性、控制和制动性能。为此，建议ABS控制算法必须分为低速控制和高速控制两部分。