Huertas-Leyva Pedro, Savino Giovanni, Baldanzini Niccolò
Dipartimento di Ingegneria Industriale, University of Florence, Firenze, Italy.
Traffic Inj Prev. 2023;24(2):132-139. doi: 10.1080/15389588.2023.2165881. Epub 2023 Jan 25.
Active safety systems such as motorcycle autonomous emergency braking (MAEB) capable of ensuring effectiveness and safe rider-vehicle interaction present many potential benefits to reduce road fatalities but also many challenges. The whole development cycle of MAEB requires research through extensive field tests that reproduce unexpected interventions or real-life driving situation before the system can be available to the end-user. This study aims to better understand the rider's kinematic response required to control the stability of the rider-motorcycle system, as well as the extent of unexpectedness perceived by participants under different degrees of awareness of automatic braking (AB) activation.
We compared responses to AB in anticipated and (un)anticipated conditions and in a condition that was intended to be genuinely unexpected (). Twenty men and women, wearing an inertial measurement unit on their upper-back, rode a scooter-type motorcycle with two front wheels simulating urban riding maneuvers on a closed test-track. Three automatic braking (AB) profiles were tested in different sessions, ranged from 3 to 5 m/s deceleration and 15 to 25 m/s braking-jerk. Differences between AB conditions were analyzed using linear mixed models.
The unanticipated condition was perceived as fairly unexpected (rated between and ). condition was on average close to the highest level of unexpectedness (). The exposure to unanticipated AB events resulted in upper-body response with larger peaks of pitch rate (0.20 to 0.77 rad/s higher) and acceleration (1.0 to 2.3 m/s higher) than those of anticipated. Participants showed less postural stability during unanticipated events taking longer both to start correcting the initial forward lean and to fully stabilize balance. Unanticipated and conditions did not differ in either the amplitude of the kinematic variables or the time-to-peak pitch rate.
The kinematic response of the rider's upper-body was found to be a reliable estimator of unexpectedness in AB. The findings suggest that unanticipated AB events while the rider engages in riding tasks can enable testing aimed at designing MAEB systems and assessing end-user acceptance in a reliable manner and within ethical safety limits.
诸如摩托车自动紧急制动（MAEB）之类的主动安全系统能够确保有效性以及安全的骑手与车辆交互，这对于减少道路死亡事故具有诸多潜在益处，但也面临许多挑战。MAEB的整个开发周期需要通过广泛的实地测试进行研究，这些测试要重现意外干预或真实驾驶情况，之后该系统才能提供给最终用户。本研究旨在更好地理解控制骑手 - 摩托车系统稳定性所需的骑手运动学响应，以及在不同程度的自动制动（AB）激活意识下参与者所感知到的意外程度。
我们比较了在预期和（非）预期条件下以及旨在真正意外的条件下对AB的反应。二十名男性和女性在上背部佩戴惯性测量单元，骑着一辆带有两个前轮的踏板式摩托车，在封闭测试轨道上模拟城市骑行操作。在不同时段测试了三种自动制动（AB）曲线，减速范围为3至5米/秒，制动急动度为15至25米/秒。使用线性混合模型分析AB条件之间的差异。
非预期条件被认为相当意外（评分在 和 之间）。 条件平均接近最高意外水平（）。与预期的AB事件相比，暴露于非预期的AB事件会导致上半身反应，俯仰率峰值（高0.20至0.77弧度/秒）和加速度（高1.0至2.3米/秒）更大。在非预期事件期间，参与者的姿势稳定性较差，开始纠正初始前倾以及完全稳定平衡所需的时间更长。非预期和 条件在运动学变量的幅度或俯仰率峰值时间方面没有差异。
发现骑手上身的运动学响应是AB中意外程度的可靠估计指标。研究结果表明，在骑手进行骑行任务时发生的非预期AB事件能够以可靠的方式并在道德安全限度内进行旨在设计MAEB系统和评估最终用户接受度的测试。
