Abstract
This paper presents a robust method for controlling the terrestrial motion of a bi-modal multirotor vehicle that can roll and fly. Factors influencing the mobility and controllability of the vehicle are explored and compared to strictly flying multirotor vehicles; the differences motivate novel control and control allocation strategies which leverage the non-standard configuration of the bi-modal design. A fifth-order dynamic model of the vehicle subject to kinematic rolling constraints is the basis for a nonlinear, multi-input-multi-output, sliding mode controller. Constrained optimization techniques are used to develop a novel control allocation strategy which minimizes power consumption while rolling. Simulations of the vehicle under closed-loop control are presented. A functional hardware embodiment of the vehicle is constructed onto which the controllers and control allocation algorithm are deployed. Experimental data of the vehicle under closed-loop control demonstrate good performance and robustness to parameter uncertainty. Data collected also demonstrate that the control allocation algorithm correctly determines a thrust-minimizing solution in real-time.
An Innovative Control Allocation Framework for a Novel Tiltrotor Aircraft
