Voting Result: 2.21590064285
Overview for Joy
Joy drone :D
Inspired by THIS IDEA this drone fits the requirements of 4 independent rotors for hover plus 1 for cruise. It has been tested that 1 main large rotor improves the energy efficiency but if it is fixed it needs extra rotors to control hover flight.
Hover rotors divide their thrust this way: the main center rotor lifts 20 kg with an oversized 4-blade propeller (it has to counterweight the fuselage and wing interference, which are minimized), plus the smaller three that have 3 kg thrust each, taking off at 86% of max thrust. The small rotors are placed in a triangle around the CG and they are tilted around the main rotor around 20º to compensate the torque created by the center propeller. Pitch, roll and yaw is an easy task with an autopilot that has to be tweaked a little bit.
The cargo bay is super easy to access and take apart, either from below or from the rear of the UAV which is cleared from obstacles. In addition it has a huge volume, batteries included inside for easy swap with the whole module, just requiring unplugging two wires or even attached with 3 magnetic pins (pull and remove) for the sake of automated loading/unloading.
Parachute and launcher seem to be in a restricted area, but since they act when the rotor is not spinning, they won't hit the blades.
A large V-tail gives the pitch and yaw in cruise flight and takes the NP back from the CG with the help of the wing swept back, making it stable enough.
This together overcomes the problem of interference of the front and main rotors and the parachute.
The landing gear is made of just one curved frame passing through the fuselage to transmit the forces. It leaves the unloading zone clear for operation.
For more information concerning materials, safety provisions, structure joints... please refer to other completed similar briefs like Mercury and Hermes. The same design guidelines, aerodynamic and performance calculations, simulations and requirements have been taken into account.