A Novel Concept for VTOL Platform Combining Variable Pitch Main Rotor and Quadrotor Configurations

Unmanned Aerial Vehicles (UAVs) have numerous applications in military, commercial, and hobby fields. Among these vehicles, drones with vertical take-off and landing (VTOL) capabilities have attracted more attention due to their specific capabilities, such as better maneuverability and hover flight. In recent years, numerous concepts emerged that are trying to propose new configurations to enhance UAV performance. This paper proposes a novel concept that integrates a single main rotor helicopter and quadrotor structure to overcome some difficulties in those applications. This suggested configuration includes a variable-pitch main rotor equipped with four smaller counterrotating rotors to overcome its opposite torque (instead of a tail rotor in helicopters) and sustain a portion of the UAV weight, which makes it possible to use a smaller main rotor. This design preserves the maneuverability of helicopters while eliminating tail rotor power loss and its asymmetric lateral force. It also enhances flight stability and maneuverability by properly using the other four rotors’ thrusts. Preliminary dynamic modeling and control system design are presented in the text, and the results show that this idea can be investigated further. Other steps are planned to be studied in the subsequent research.