A scooter has a body that can travel on the ground, and the body is electrically connected to an emergency stop assist system. The auxiliary system is a control unit, a motor controller that determines the traveling speed of the vehicle body, and a front (or rear) ultrasonic ranging unit that emits pre-sound waves toward the front (or rear) side of the vehicle body. When the ultrasonic wave encounters an obstacle and returns a reflected wave, the front (or rear) ultrasonic ranging unit receives the reflected wave and converts it into a distance signal, and the distance signal is transmitted to the control unit to perform a distance measurement with respect to a preset value. If the preset value is not reached, the control unit determines that the vehicle body is at a safe distance and does not execute the deceleration command. When the preset value is reached or exceeded, the control unit sends a signal to the motor controller to stop the vehicle body from decelerating and stopping, thereby effectively improving the safety of the scooter.一種代步車，其有一可在地面行進的車體，該車體電性連接一緊急停止的輔助系統。該輔助系統一控制單元、一決定車體行進速度的馬達控制器、一朝向車體前(或後)方發射前超音波的前(或後)超音波測距單元。當超音波遭遇障礙物返回反射波，該前(或後)超音波測距單元接收反射波轉換為一距離訊號，該距離訊號傳輸至控制單元比對一預設值進行遠近距離判斷。未達預設值，該控制單元判斷車體在安全距離，不執行減速命令。達到或超出預設值，該控制單元送出訊號至馬達控制器，操作車體減速、煞車停止，有效提升代步車的安全性。
