A novel tandem-type soft unmanned aerial vehicle: Mechanism design, performance validation and implementation

Helium-filled blimps have been one of the solutions to increase the flight time and improve the safety of flying robots. However, previous developments still have the possibility of crash and casualty because of exposed propellers. In this study, a tandem-type soft Unmanned Aerial Vehicle (UAV), called 'S-CLOUD II' is presented. Mounting two rotors at a hole penetrating inside the blimp resolves the crash risk with obstacle or people. While the buoyancy induced by Helium reduces the flight weight, flight efficiency increases. Also, we developed a novel rotor control mechanism, called 'omni-rotor' whose rotor axis can rotate about each axis with two servo motors. Due to this mechanism, S-CLOUD II can fly like usual quadrotor without tilting the platform. After describing the design and mechanism of the platform, its principles of operations are explained. Also, the experiments for flight performance are introduced and its validation based mounted sensor is followed. Finally, application cases with S-CLOUD II and its future works are also addressed.