Kegunaan pesawat udara tanpa pemandu berkuasa solar sekian menggantikan pesawat udara tanpa pemandu konvensional disebabkan kelestarian dan ketahanan yang tinggi. Kemampuan pesawat udara tanpa pemandu berkuasa solar melakukan tugas-tugas tertentu dengan kos yang lebih rendah membolehkan pesawat tersebut sesuai untuk digunakan di pelbagai bidang. Beberapa kajian berkaitan perancangan laluan udara pesawat tanpa pemandu telah dilakukan melalui pendekatan yang berbeza. Namun, perbandingan antara laluan udara berasaskan corak dan laluan udara berasaskan algoritma masih tidak mencukupi. Dalam kajian ini, tiga cara perancangan laluan udara telah diimplikasikan di 12 lokasi rawak yang teletak sama rata di muka Bumi. Parameter-parameter penting seperti kesinaran solar, ketumpatan udara dan aras tinggi muka bumi yang mempengaruhi prestasi pesawat udara tanpa pemandu serta liputan muka Bumi telah dipertimbangkan dalam kajian ini. Sepanjang misi liputan muka bumi selesai, altitud pesawat udara tanpa pemandu dikekalkan pada 100 m atas permukaan Bumi dan halaju dikekalkan pada tahap minimum. Ketiga-tiga cara perancangan laluan udara telah dibandingkan antara satu sama lain berdasarkan nisbah kumulatif kesinaran solar kepada jarak yang telah diliputi oleh pesawat udara tanpa pemandu. Di samping itu, pengecas bateri dipastikan lebih daripada 10% supaya pesawat udara tanpa pemandu dapat melaksanakan penerbangan berterusan. Tiga cara perancangan laluan udara yang telah dikaji dalam kajian ini adalah corak sistematik, pergerakan rawak dan pergerakan berdasarkan algoritma evolusi pembezaan. Bagi setiap corak sistematik, beberapa lokasi pelancaran pesawat udara telah dikaji. Bagi pergerakan rawak dan pergerakan berasaskan algoritma evolusi pembezaan, pesawat udara tanpa pemandu telah dilancarkan dari koordinat yang terletak di tengah setiap lokasi. Simulasi melalui MATLAB mendedahkan bahawa pergerakan berasaskan algoritma evolusi pembezaan mengurangkan bilangan langkah yang diambil pesawat udara tanpa pemandu sebanyak 91.38% jika dibandingkan dengan pergerakan rawak. Corak sistematik yang tidak bertindih lebih efisien daripada pergerakan berasaskan algoritma evolusi pembezaan sebanyak 48.11% manakala corak sistematik bertindih mengurangkan bilangan langkah sebanyak 47.18%. Cara perancangan laluan udara yang paling bersesuaian berbeza bagi setiap lokasi. Secara keseluruhan, corak sistematik muncul sebagai cara perancangan laluan udara terbaik bagi kebanyakan lokasi manakala corak mendatar muncul sebagai corak penerbangan paling bersesuaian bagi kebanyakan lokasi.
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The usage of solar-powered unmanned aerial vehicle (UAV) over conventional UAV has constantly been increasing due to high sustainability and endurance. The ability of solar-powered UAV to perform certain tasks at a lower cost makes it suitable to be used in a wide range of fields. Various works on UAV path planning have been carried out through different approaches; however, these research lack assessment between a systematic pattern-based path and evolutionary integrated algorithm-based path, to understand the impact in global path planning. In this research, three types of methods are investigated at 12 random and evenly distributed locations around the Earth globe. The target area for coverage of each location has been set as a square area, where each area coverage is 1.12% of the whole earth surface area. Important parameters such as solar irradiance, air density and earth elevation that influence the performance of solar-powered UAV and the ability to complete ground coverage are assessed in this research. The solar-powered UAV’s altitude was maintained at 100 m above ground level and simulated to fly at minimum cruise velocity throughout the mission. All three methods were compared with each other based on cumulative solar irradiance to distance travelled ratio. Here, the UAV battery SOC was conditioned to be more than 10% to ensure a continuous flight throughout the mission. The three methods investigated in this work are 1) systematic pattern (pre-determined path), 2) random movement and 3) Differential Evolution (DE) integrated algorithm movement. For each of the systematic pattern, several different launch points were tested. In contrast, for random movement and DE integrated algorithm movement, the UAV is launched from the center of each location’s region. Simulation through MATLAB reveals that DE integrated algorithm movement reduces the number of steps taken by 91.38% as compared to random movement. Non-overlapping systematic patterns are better than DE integrated algorithm movement by 48.11%. In comparison, overlapping in systematic patterns are better by 47.18% in terms of the number of steps taken to complete each ground location. The most suitable method to be used among the three methods experimented varies according to location. Overall, a systematic pattern emerges as the best method for most of the locations. In contrast, the horizontal pattern emerges as the most suitable pattern for more locations compared to other patterns.
Comparison of path planning methods for solar-powered uav in 12 different locations worldwide / Sugan Nagappan