A Real-Time Control Barrier Function-Based Safety Filter for Motion Planning with Arbitrary Road Boundary Constraints

IEEE International Conference on Intelligent Transportation Systems (ITSC), pp. 2818–2825

Abstract

We present a real-time safety filter for motion planning, including those that are learning-based, using Control Barrier Functions (CBFs) to provide formal guarantees for collision avoidance with road boundaries. A key feature of our approach is its ability to directly incorporate road geometries of arbitrary shape that are represented as polylines without resorting to conservative overapproximations. We formulate the safety filter as a constrained optimization problem as a Quadratic Program (QP), which achieves safety by making minimal, necessary adjustments to the control actions issued by the nominal motion planner. We validate our safety filter through extensive numerical experiments across a variety of traffic scenarios featuring complex road boundaries. The results confirm its reliable safety and high computational efficiency (execution frequency up to 40 Hz). Code reproducing our experimental results and a video demonstration are available at github.com/bassamlab/SigmaRL.

Authors 3

1. Jianye Xu Aachen Department of Computer Science

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Department of Computer Science,Germany

2. Chang Che Aachen Department of Computer Science

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Department of Computer Science,Germany

3. Bassam Alrifaee

   Universität der Bundeswehr München

   Affiliation as printed

   University of the Bundeswehr,Department of Aerospace Engineering,Munich,Germany