Stability and performance analysis of unmanned aerial vehicles: Quadrotor against Hexrotor

Multirotor helicopters are very powerful flying robots used in many applications, but their lack is robustness. A fail in any of their rotors can drive the helicopter to fall. In this study two different micro-helicopter structures are analysed, a standard Quadrotor and a Hexrotor. An uncertainty model is generated and a robust controller is designed. The structured singular value μ_Δ is used to test the robust stability and performance of these two plants, obtaining better results for Hex than Quadrotor. At the end of the study, a set of flight tests, where some of the motors are partially damaged, is presented confirming the analysis of μ_Δ. Results of this study show Hexrotor as a very interesting structure for unmanned aerial vehiclesbecause of its stability and performance characteristics compared with Quadrotor.