An Energy Analysis of Quadrotors with Cable-Suspended Payloads

This paper aims to perform a qualitative energy analysis of quadrotors with cable-suspended payloads. First, the dynamics model of this system is presented, then the concept of energy quotient is introduced to help qualitatively assess quadrotor's energy consumption without prior knowledge of quadrotor-specific parameters such as propeller and motor specifications. After that, a detailed mathematically-oriented energy analysis is preformed to investigate the effect of payload mass, cable length, quadrotor's polynomial trajectory degree and average acceleration on quadrotor's energy consumption. The analysis is enforced by simulations and validated experimentally. The results show that increasing payload mass, polynomial trajectory's average acceleration and/or polynomial degree increases quadrotor's energy consumption monotonically. It also shows that there exists an optimized cable length, at which, quadrotor's energy consumption is minimum.