Search Results (5)

Unmanned aerial vehicles (UAVs) have two predominant configurations: fixed-wing, efficient in cruise flight and with long endurance, but dependent on runways or large areas for operation; and multirotor, capable of vertical take-offs and landings and precise maneuvers, although limited by their shorter range and efficiency. Hybrid VTOL UAVs, and especially QuadPlane UAVs, offer an intermediate solution, combining the aerodynamic efficiency of the fixed-wing UAV with the maneuverability of the multirotor through simple and versatile architecture. This work develops a complete and unified dynamic model of the Skywalker VTOL UAV, derived from the Skywalker X8 with the addition of four vertical rotors. The resulting dynamic model is formulated using a system of nonlinear ODEs, which realistically and comprehensively describe the vehicle behaviour, considering that the inputs from the airplane and quadcopter sections can act simultaneously, thus improving its efficiency. Implementation in MATLAB-Simulink and validation through simulations under equilibrium conditions and with varying inputs confirm the expected behaviour of a QuadPlane. This model provides a strong foundation for developing advanced multivariable control, guidance, and navigation strategies for next-generation hybrid UAVs. Full article

The vertical take-off and landing (VTOL) of unmanned aerial vehicles (UAVs) is extensively employed in various sectors. To ensure adherence to design specifications and mission requirements, it is vital to verify flight control and system performance using an accurate dynamic model specific to UAV configuration. Traditionally, engineers follow a sequential approach in UAV design, which involves multiple design iterations comprising CAD drawings, material collection, fabrication, flight tests, system identification, modifications, dynamic model extraction, checking if the results meet requirements, and then repeating the process. However, as UAVs become larger, heavier, and more enduring to meet complex system demands, the costs and time associated with each design iteration of creating a new UAV escalate exponentially. The bare-airframe dynamics of the UAV are crucial for engineers to design a controller and validate handling quality and performance. This paper proposes a novel method to accurately predict the dynamic model of the bare airframe for quadrotor UAVs without physically constructing them in the real world. The core concept revolves around converting the quadrotor UAV design from CAD software into a UAV model within an X-Plane simulator. Leveraging the CIFER software’s two key features—frequency domain system identification and parametric model fitting—the unstable bare-airframe dynamics are extracted for both the UAV model in X-Plane and a real-world DJI 450 UAV with the same physical configuration. This paper provides essential parameters and guidance for constructing a 92% high-fidelity dynamic model of the given UAV configuration in X-Plane. The flight test results demonstrate excellent alignment with the simulation outcomes, instilling confidence in the effectiveness of the proposed method for designing and validating new UAVs. Moreover, this approach significantly reduces the time and cost associated with the traditional design process, which requires an actual build of the UAV and many flight tests to verify the performance. Full article

With the increasing popularity of vertical take-off and landing unmanned aerial vehicles (VTOL UAVs), a new problem arises: pilot training. Most conventional pilot training simulators are designed for full-scale aircrafts, while most UAV simulators are just focused on conceptual testing and design validation. The X-Plane flight simulator was extended to include new functionalities such as complex wind dynamics, ground effect, and accurate real-time weather. A commercial HIL flight controller was coupled with a VTOL convertiplane UAV model to provide realistic flight control. A real flight case scenario was tested in simulation to show the importance of including an accurate wind model. The result is a complete simulation environment that has been successfully deployed for pilot training of the Marvin aircraft manufactured by FuVeX. Full article

A vertical take-off and landing plane (VTOL plane) is a fixed-wing unmanned aerial vehicle (FWUAV) configuration with the ability to take off and land vertically. It combines the benefits of fixed-wing and multirotor configurations, which gives it a high cruising range and independence from a runway. This configuration requires arms as mountings for the VTOL’s motors. This study discusses the design of a VTOL Plane with various VTOL arm configurations, and a computational fluid dynamics (CFD) simulation was conducted to find out which configuration performs the best aerodynamically. The VTOL arm configurations analyzed were a quad-plane, a twin-tail boom, a tandem wing, and a transverse arm. The interpreted performances were the lift and drag performances, stall conditions, flight efficiency, stability, and maneuverability. The relative wind directions toward the longitudinal axis of the UAV, which are the sideslip angle and the angle of attack, were varied to simulate various flying conditions. The results showed that the twin tail-boom is the most advantageous based on the interpreted performances. Full article

A Vertical Take-Off and Landing-Plane (VTOL-Plane) is an Unmanned Aerial Vehicle (UAV) that combines multirotor and fixed-wing configurations. It has a good cruise range compared to a VTOL vehicle. Furthermore, it can take-off and land vertically. This technology is ideal for surveillance/monitoring missions and transmitting data in real-time. This study discusses the design of a VTOL-Plane with a preset Design Requirement Objectives (DRO), namely a Maximum Take-Off Weight (MTOW) of 14 kg, a cruise speed of 23 m/s, and a cruising range of 6 h. To maximize the performance, the empennage configurations on the VTOL-Plane varied, and then a Computational Fluid Dynamics (CFD) simulation was carried out. The empennage configurations analyzed were a U-shaped boom, an inverted U-shaped boom, an inverted V-tail boom, and a semi-inverted V-tail boom. The interpreted performance related to the stalling angle, flight efficiency, stability, stall speed, and maneuverability. The relative wind directions toward the longitudinal axis of the UAV, also called the sideslip angle, were varied. The CFD simulation results showed that the empennage configuration of the inverted U-shaped boom is suitable for a surveillance mission. This article also optimized the final empennage design by adding a vertical fin to improve stability. Full article