AHS control laws for platoons leaders

In the AHS architecture of the California PATH program traffic is organized into platoons of closely spaced vehicles. Whenever platoons are formed or broken up, the large relative motion between platoons, increases the risk of high relative velocity collisions. In this paper we derive a safety region for the relative velocity between two platoons. By guaranteeing that the relative velocity between platoons remains in this region, impacts of high relative velocity can be avoided. For each one of the four control laws that a platoon leader can perform in normal operation, a desired velocity profile for the platoon that satisfies safety and time-optimality requirements is derived. A nonlinear velocity controller is designed to track the desired velocity profile within a given error bound. When safety is not compromised, this controller keeps the acceleration and jerk of the vehicles in the platoon within comfort limits.