Dynamic modeling and analysis of a VTOL freewing concept

The freewing aircraft is an airplane with the wing placed on a hinged bearing about the pitch axis that allows for free rotation with respect to the fuselage body. The freewing only differs from a conventional airplane in that the wing is free to rotate. The 70 year old concept, through various studies, has been shown that by placing the wing on a free- to-rotate hinge, it effectively reduces the inertia of the wing making it easier for the wing to adjust to turbulence. The work described in this paper makes two large contributions to past freewing work. The first is the motors are placed on the wing which allows for vertical takeoff and landing (VTOL). The second is a different dynamic analysis approach that uses multi-body dynamics and uses hinge constraints as part of the state vector which allow for an easier way of solving the equations of motion. Data is shown for how the longi- tudinal modes change when varying design parameters. Simulation data is also presented highlighting the VTOL aspect of the vehicle.