TOYOTA Sienna Incident

The May Mobility vehicle (Ego) approaches a turn with a trailing vehicle following closely behind. The May planner initially selects a trajectory it believes will safely complete the turn. However, as the Ego begins the turn, it re-evaluates the situation and detects a significant risk of striking the curb. At that point, the planner shifts focus from avoiding the curb entirely to minimizing the severity of a potential curb strike. To reduce speed before the expected contact, the Ego brakes at €“3.5 m/s²). Because the trailing vehicle is following so closely, this deceleration makes a rear-end collision likely. The Ego predicts a potential rear-end collision and elects to reduce brake force to lessen the impact severity. Moments later, the trailing vehicle strikes the rear driver-side bumper of the Ego and then drives away. Future improvements are underway to give the planner a policy option to steer away from curbs. This new capability will help the vehicle avoid situations where braking becomes the only remaining way to manage close curb proximity.