WITHDRAWN: A Novel Turning by Yaw Flight Control Algorithm for VTOL Wing-in-Ground (WIG) Crafts

Low-altitude turning flights are both essential and challenging for Wing-in-Ground (WIG) crafts. This paper proposes a novel Turning by Yaw Control (TBYC) algorithm, which is subsequently validated through flight tests. Unlike conventional aileron and rudder-based control methods, TBYC utilizes vectored propeller thrust as its primary control mechanism. First, the mathematical formulations of TBYC were developed, and the flight control firmware was customized within the PX4 framework. Next, a WIG-craft prototype equipped with vertical takeoff and landing (VTOL) capability was designed and constructed to verify the feasibility and performance of TBYC by direct flight test. The test results indicate that the TBYC achieves a stable turning rate of up to 250 deg/s during hovering, with minimal wingtip height variation of 0.1 m across a wingspan of 2.3 m. Furthermore, the TBYC enables stable level turns, maintaining a wingtip height variation of 0.187 m at a flight speed of 12 m/s. At the same flight speed, the TBYC produces a significantly smaller turning radius and reduced wingtip height variation compared to conventional banked turns. The TBYC proves to be an effective control strategy for executing rapid level turns, minimizing the risk of wingtip collisions with the water surface, and substantially enhancing the agility and safety of WIG crafts.