This paper develops an active sensing and estimation system for protecting the rider of an e-scooter from car-scooter collisions. The objective is to track the trajectories of cars behind the e-scooter and predict any real-time danger of car-scooter collision. If the danger of a collision is predicted, then a loud car-horn-like audio warning is sounded to alert the car driver to the presence of the scooter. A low-cost (∼$100) single-beam laser sensor is chosen for measuring the positions of cars behind the scooter. The sensor is mounted on a stepper motor and the region behind the scooter is scanned to detect vehicles. Once a vehicle is detected, its trajectory is tracked in real-time by using feedback control to focus the orientation of the laser sensor such as to make measurements of the right front corner of the vehicle. A nonlinear vehicle model and a nonlinear observer are used to estimate the trajectory variables of the tracked car. The estimated states are used in a receding horizon controller that controls the real-time position of the laser sensor to focus on the vehicle. The developed system is implemented on a Ninebot e-scooter platform. Extensive experiments conducted with multiple vehicle maneuvers show that the closed-loop system is able to accurately track vehicle trajectories and provide audio alerts to prevent collisions. This paper constitutes the first-ever development of active rider protection technology for the protection of e-scooters.

中文翻译：

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智能电动滑板车，内置后车轨迹估计，以保护骑手


本文开发了一种主动传感和估计系统，用于保护电动滑板车的骑手免受汽车与滑板车碰撞的影响。目标是跟踪电动滑板车后面的汽车轨迹并预测汽车与滑板车碰撞的实时危险。如果预测到发生碰撞的危险，则会发出类似于汽车喇叭的声音警告，以提醒汽车驾驶员踏板车的存在。选择低成本（约 100 美元）单光束激光传感器来测量踏板车后面的汽车位置。该传感器安装在步进电机上，扫描踏板车后面的区域以检测车辆。一旦检测到车辆，就会通过反馈控制来实时跟踪其轨迹，以聚焦激光传感器的方向，例如对车辆的右前角进行测量。非线性车辆模型和非线性观测器用于估计履带车的轨迹变量。估计的状态用于后退地平线控制器，该控制器控制激光传感器的实时位置以聚焦在车辆上。开发的系统在 Ninebot 电动滑板车平台上实现。对多种车辆操纵进行的大量实验表明，闭环系统能够准确跟踪车辆轨迹并提供音频警报以防止碰撞。本文首次开发了用于保护电动滑板车的主动骑手保护技术。