Design of a solar UAV for persistent wildlife monitoring

• Autor(a) principal: Santos, Rúben David Almeida
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.6/11697
• topic: Metodologia de Projeto; Projeto de Aeronaves; Uav Solar; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Aeronáutica

Since the beginning of human flight, one of the most difficult goals has been to make an aircraft to stay aloft for very long periods of time. One of the solutions to this problem is to harvest solar energy during flight to increase the flight time and ideally achieve perpetual flight. Generally a solar aircraft does not need to be refuelled or recharged every time it has to start a mission, instead it collects solar energy during the daytime for flight and to recharge the battery for night flight. This process reduces the need for daily operations. This thesis presents a methodology to design a solar aircraft capable of flying for long periods of time which may be dedicated to monitoring wildlife. The developed methodology builds on previous works by Noth by adding the possibility of analysing several wing and tail airfoils as well as computing the corresponding aerodynamic characteristics to have more reliable results. It also includes a second phase where a more detailed analysis is performed to provide more reliable results for a given mission profile defined by a high-altitude day-time segment and a low altitude night flight. To make use of this methodology, the design process of a prototype is presented. This prototype serves to test the concept behind a mission of a fixed wing aircraft that flies at a latitude of 30oN to monitor wild animals for very long periods of time. The aircraft should also be able to fly any day of the year at this latitude. This prototype is made modular, so the wingspan can be increased or decreased depending on the energy needs along the year. At this latitude, the winter solstice has 10.2 hours of daylight and 13.8 hours of nighttime. Despite the prototype only flying from 1 hour before sunrise to 3 hours after sunset, this data is important for the full-scaled version. The design of a solar aircraft capable of flying several days is a challenging, complex and multidisciplinary problem. This work shows that even for a very light payload, a relatively large wing aircraft is needed due to the very low wing loading required for high efficiency. Also, parameters such as battery energy density, solar panel area ratio, structural mass, mission profile, and mission location and time of the year have important effects on the final design size and mass.