Search papers, labs, and topics across Lattice.
This paper introduces Safety Enhanced Passivity-Based Nonlinear Model Predictive Control (SEP-NMPC) for quadrotors carrying slung payloads, ensuring stability and safety in cluttered environments. Stability is achieved by incorporating a strict passivity inequality derived from an energy storage function with adaptive damping into the NMPC formulation. Safety is guaranteed using high-order control barrier functions (HOCBFs) to maintain separation from static and dynamic obstacles.
Achieve formally guaranteed safe and stable slung-load UAV flight in cluttered environments by unifying passivity-based control with high-order control barrier functions within an MPC framework.
Model Predictive Control (MPC) is widely adopted for agile multirotor vehicles, yet achieving both stability and obstacle-free flight is particularly challenging when a payload is suspended beneath the airframe. This paper introduces a Safety Enhanced Passivity-Based Nonlinear MPC (SEP-NMPC) that provides formal guarantees of stability and safety for a quadrotor transporting a slung payload through cluttered environments. Stability is enforced by embedding a strict passivity inequality, which is derived from a shaped energy storage function with adaptive damping, directly into the NMPC. This formulation dissipates excess energy and ensures asymptotic convergence despite payload swings. Safety is guaranteed through high-order control barrier functions (HOCBFs) that render user-defined clearance sets forward-invariant, obliging both the quadrotor and the swinging payload to maintain separation while interacting with static and dynamic obstacles. The optimization remains quadratic-program compatible and is solved online at each sampling time without gain scheduling or heuristic switching. Extensive simulations and real-world experiments confirm stable payload transport, collision-free trajectories, and real-time feasibility across all tested scenarios. The SEP-NMPC framework therefore unifies passivity-based closed-loop stability with HOCBF-based safety guarantees for UAV slung-payload transportation.
