Trajectory Generation for Aggressive Waypoint Transitions by an Autonomous Helicopter

This paper considers the problem of generating optimal guidance trajectories for high-speed waypoint transitions by an autonomous helicopter. Given a set of waypoints and a desired order for passing through them, an optimal control problem is solved using collocation for every pair of consecutive waypoints. The linear hover model of the Yamaha R-50 helicopter is employed in the optimal control problem, with sixteen states and four control inputs. The trajectory of every state and control variable is constrained to satisfy the physical limitations of the helicopter. The helicopter is also required to satisfy a corridor constraint between waypoints, and to pass sufficiently close to each end waypoint at near hover speed. To generate aggressive transitions between consecutive waypoints, variable flight time is considered and compared to fixed flight time. Numerical experiments show aggressive transitions for the variable flight time formulation, with the control inputs reaching saturation levels between waypoints.