Global Navigation Satellite System (GNSS) Independent Navigation for Unmanned Aerial Vehicles (UAV)

Öz

The ability of Unmanned Aerial Vehicles (UAV) to perform autonomous navigation depends on the accurate determination of their positions provided by the Global Navigation Satellite System (GNSS). For position determination and environmental orientation during flight, UAVs are usually equipped with electronic equipment such as GNSS, Inertial Measurement Unit (IMU), gyroscope and accelerometer. However, the GNSS signal may be lost or distorted due to poor weather, obstacles or terrain, the unfavorable position of satellites, spoofing and jamming. In such cases of GNSS signal loss or deterioration, the IMU alone becomes unable to provide reliable UAV location information. Especially in cases where there is not enough visibility and the UAV cannot be brought to the take-off point by manual operation, the loss of the GNSS signal causes great losses. In this paper, GNSS independent flight and navigation studies are included. It is seen that the use of hybrid navigation solutions has great importance in GNSS independent UAV flights.

Anahtar Kelimeler

• UAV
• GNSS-independent
• navigation

İnsansız Hava Araçları (İHA) İçin Küresel Navigasyon Uydu Sistemi (GNSS) Bağımsız Navigasyon

Öz

İİnsansız Hava Araçlarının (İHA) otonom navigasyon yapabilmesi, Global Navigation Satellite System (GNSS-Küresel Navigasyon Uydu Sistemi) ile sunulan konumlarının doğru olarak belirlenmesine bağlıdır. Uçuş esnasında konum belirlemek ve çevresel oryantasyon için İHA’lar genellikle GNSS, Inertial Measurement Unit (IMU, Ataletsel Ölçüm Birimi-AÖB), jiroskop ve ivmeölçer gibi elektronik ekipmanlarla donatılmıştır. Ancak, kötü hava koşulları, engellerin veya arazilerin varlığı, uyduların elverişsiz konumu, aldatma (spoofing) ve karıştırma (jamming) nedeniyle GNSS sinyali kaybolabilir veya bozulabilir. Bu gibi GNSS sinyali kaybolma veya bozulma durumlarında, AÖB tek başına güvenilir İHA konum bilgisi sağlayamaz hale gelmektedir. Özellikle yeterli görüşün olmadığı ve manuel kullanım ile İHA’nın kalkış noktasına getirilemediği durumlarda GNSS sinyalinin kaybolması büyük kayıplara neden olmaktadır. Bu çalışmada, yapılan GNSS bağımsız uçuş ve navigasyon çalışmalarına yer verilmiştir. Hibrit navigasyon çözümlerinin kullanılmasının GNSS bağımsız İHA uçuşlarında büyük öneme sahip olduğu görülmektedir.

Anahtar Kelimeler

• İHA
• GNNS-bağımsız
• navigasyon

Kaynakça

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