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Vertical Take-Off and Landing (VTOL) Unmanned Aerial Vehicles (UAVs) provide a versatile platform well-suited to applications requiring the efficiency of fixed-wing flight with the maneuverability of a multicopter. Prior work has introduced the concept of using solar energy harvesting using photovoltaic cells embedded in the wings of the vehicle to perform self-recharge in the field when landed and at rest. This work demonstrates a further extension of this concept by optimizing the VTOL aircraft for maximum input-to-output power ratio, such that continuous flight is possible for the majority of a typical day with good sunlight. By also adding amphibious design elements, a transoceanic flight cycle is proposed. The candidate aircraft design is shown with estimated and actual behavioral and performance data for hovering and forward flight. Artwork for design elements such as the tiltrotor nacelle design and interchangeable avionics pod are shown.
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The MiniHawk-VTOL: Design, Modeling, and Experiments of a Rapidly-prototyped Tiltrotor UAV
This work addresses the rapidly-prototyped design of a small Tricopter/Fixed-Wing Vertical Take-Off and Landing UAS with solar-recharge-capability, capable of repeatedly landing, recharging, and taking off, without need for physical intervention or externally placed maintenance devices or platforms. The design uses Fused Deposition Modeling 3D printing to rapidly prototype and fabricate the majority of the aircraft structures and parts. Provisions are made for carrying high-level single board computing solutions, or other similar payloads. Details are provided for mechanisms, aerodynamic geometry, solar cell integration and manufacturability. The design is analyzed to estimate inertial moments, aerodynamic performance, and static and dynamic stability. Simulation models for the Gazebo and RealFlight environments are provided, targeting Software-In-The-Loop architectures that run the ArduPilot and PX4 flight stacks. A flight testing methodology is developed, and results are presented with multiple prototype vehicles constructed. We finally contribute all production definitions, files, and models as open-access resources, with the goal of supporting and promoting migratory/swarming behavior and autonomy research.
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- Award ID(s):
- 2008904
- PAR ID:
- 10296732
- Date Published:
- Journal Name:
- 2021 International Conference on Unmanned Aircraft Systems
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Unmanned Aerial Vehicles (UAVs) hold immense potential across various fields, including precision agriculture, rescue missions, delivery services, weather monitoring, and many more. Despite this promise, the limited flight duration of the current UAVs stands as a significant obstacle to their broadscale deployment. Attempting to extend flight time by solar panel charging during midflight is not viable due to battery limitations and the eventual need for replacement. This paper details our investigation of a battery-free fixed-wing UAV, built from cost-effective off-the-shelf components, that takes off, remains airborne, and lands safely using only solar energy. In particular, we perform a comprehensive analysis and design space exploration in the contemporary solar harvesting context and provide a detailed accounting of the prototype’s mechanical and electrical capabilities. We also derive the Greedy Energy-Aware Control (GEAC) and Predictive Energy-Aware Control (PEAC) solar control algorithm that overcomes power system brownouts and total-loss-of-thrust events, enabling the prototype to perform maneuvers without a battery. Next, we evaluate the developed prototype in a bench-top setting using artificial light to demonstrate the feasibility of batteryless flight, followed by testing in an outdoor setting using natural light. Finally, we analyze the potential for scaling up the evaluation of batteryless UAVs across multiple locations and report our findings.more » « less
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Accepted Manuscript1.0
- Conference Paper:
- The DOI is not currently available.
