Tracking Control of Multi-Input Multi-Output Multirotor Unmanned Aerial Vehicles with Auxiliary Systems

Abstract

We research control schemes for unmanned aerial vehicles (UAVs) with propulsion, steering and power modules. Physical limits, aerodynamic instabilities, blade flapping, cross-axis coupling, data heterogeneity and other factors affect design. In multirotor UAVs, the differential thrust is regulated by changing the angular velocity of propellers, rotated by brushless electric motors. Voltages applied, phase currents, propeller speed and thrust cannot exceed specific limits. To accomplish aerial photography, airborne intelligence, surveillance, reconnaissance and support missions, multirotor and fixed-wing vehicles integrate active electronically scanned array radar, light detection and ranging modules, transceivers, controllers-drivers, steered pylon mounts, dc-dc regulators, battery pack, charger, etc. The differential thrust is regulated by changing propellers’ angular velocity. We design constrained tracking control laws to govern aerial systems regulating state and error dynamics. Minimizing design-consistent functionals with range-restricted descriptive bounded functions, limits are accounted for by integrands, and control laws are analytically designed. Nonquadratic functionals with domain-specific positive-definite integrands and Hamiltonians admit closed-form solutions. The Hamilton-Jacobi equation is satisfied by continuous positive-definite return functions. Descriptive state-space models and error governance support a design to ensure optimal tracking error evolution. Bounded algorithms with state and tracking error feedback guarantee system optimality subject to minimized functionals. Control schemes, optimization tools, and algorithms are experimentally substantiated for a quadrotor helicopter. Controllers are designed and characterized for flight control systems, direct-drive steering mount pylons, brushless motors, and dc-dc switching regulators.