Collision Avoidance and Liveness of Multi-agent Systems with CBF-based Controllers
Mrdjan Janković, Mario Santillo · 2021 60th IEEE Conference on Decision and Control (CDC) · 2021
In this paper we consider multi-agent collision avoidance using Control Barrier Functions (CBF). One contribution is a comparison of several CBF-based control policies proposed in the literature and a new one proposed here for completeness. We study tradeoffs between a level of safety guarantee and liveness – the ability to reach a destination in short time without large detours or gridlock – using the centralized controller as the benchmark. The new policy (CCS2) straddles the space between policies with only local control available and a more complex Predictor-Corrector for Collision Avoidance (PCCA) policy and tries to answer how much performance might be lost if the policy does not use estimates or measurements of other agents’ control actions. Another contribution of the paper is that it establishes feasibility for the centralized, PCCA and CCS2 policies. Monte Carlo simulations show that decentralized, host-only control policies lack liveness compared to the ones that use everyone’s control inputs in the calculations (whether they are local copies or not) and that the PCCA policy, which runs with incomplete information, performs equally as well as the centralized.