Energetic analysis and optimization of a bi-modal rolling-flying vehicle

Abstract

This paper presents an energetics analysis of a bi-modal vehicle that is capable of rolling and flying. The vehicle under consideration combines the mobility and maneuverability of rotary wing flight with the efficiency of rolling locomotion. The energetics analysis uses blade element momentum theory and an electromechanical motor model to predict the electrical power consumption of the propulsion system and the maximum range of the vehicle. The performance of the rolling-flying vehicle (RFV) is compared to that of a conventional quadrotor, with the RFV having a cost of transport approximately one tenth that of the quadrotor. Analysis demonstrates that rolling locomotion provides an additional degree of control which permits optimizing the vehicle’s operation to either maximize range or minimize power. Simulations reveal a complex dependence of power on vehicle velocity and angle of attack, which informs the optimization strategy. Methods for optimization are discussed. This optimization strategy negates the need for an explicit locomotion mode decision as the transition from rolling to flying occurs naturally as a byproduct of the optimization.