LatentCBF: A Control Barrier Function in Latent Space for Safe Control

Abstract

Safe control is crucial for safety-critical autonomous systems that are deployed in dynamic and uncertain environments. Quadratic-programming-control-barrier-function (QP-CBF) is becoming a popular tool for safe controller synthesis. Traditional QP-CBF relies on explicit knowledge of the system dynamics and access to all states, which are not always available in practice. We propose LatentCBF (LCBF), a control barrier function defined in the latent space, which only needs an agent's observations, not full states. The transformation from observations to latent space is established by a Lipschitz network-based AutoEncoder. In addition, the system dynamics and control barrier functions are all learned in the latent space. We demonstrate the efficiency, safety, and robustness of LCBFs in simulation for quadrotors and cars.