TRAJECTORY PLANNING SYSTEMS FOR AUTONOMOUS VEHICLES

Aspects of the disclosure may enable an autonomous vehicle to perform evasive maneuvers in order to avoid potential collisions. For instance, a vehicle may be controlled in an autonomous driving mode using a first trajectory generated by a first planning system. Information identifying a characteristic of a road user in an environment of the vehicle may be received and used to determine whether to generate a new behavior prediction for the road user or to use a prior determined behavior prediction. While using the first trajectory, a second planning system may be used to generate a second trajectory based on the determination. The second trajectory may be compared to the first trajectory. The vehicle may be controlled in the autonomous driving mode based on a result of the comparing.