GPS YER KONTROL NOKTALARI KULLANILARAK LiDAR VERİSİNİN DOĞRULUK ANALİZİ

Öz

Günümüzde, harita üretiminde kullanılan çalışmalarda, geleneksel ölçüm tekniklerinden farklı olarak hem daha hızlı, hem de doğruluğu daha yüksek yeryüzü verisi elde etme çabaları gün geçtikçe artmaktadır. Bu çalışmada, elektromanyetik spektrumun 1.064nm yakın infrared bölgesinde algılama yapan bir Uzaktan Algılama Tekniği olan Hava LiDAR teknolojisinin, yatay ve düşey doğruluğunun RTK/GPS verileri ile (Real Time Kinematik- Global Positioning System) test edilmesi amaçlanmıştır. Bu kapsamda, Türkiye’nin Doğu Karadeniz bölgesinde yer alan Artvin İli Borçka ilçesinde 2x2 km2 büyüklüğünde bir ormanlık bölge, çalışma alanı olarak seçilmiştir. Çalışmada, RTK/GPS ile elde edilmiş Yer Kontrol Noktaları (YKN) ile bu noktaların karşılık geldiği LiDAR noktalarının belirlenmesi için arama çapı yöntemi geliştirilmiş ve ayrıca, değişik arazi kategorileri için karşılaştırmalı test sonuçları ortaya konulmuştur. Çalışmanın sonucunda, düşey hata miktarı (KOHz) normal dağılımda 0.20 m olarak ve %95 güven aralığında düşey doğruluk (doğrulukz) ise 0.39m olarak bulunmuştur. Yatay hata (KOHr) normal dağılımda minimum 0.36m, maksimum 1.01m; yatay doğruluk (doğrulukr) ise %95 güven aralığında minimum 0.62m, maksimum 1.75m düzeyinde gerçekleşmiştir. Bu çalışmada kullanılan Hava LiDAR verisi için düşey doğruluk, yatay doğruluğa göre yaklaşık iki kat daha prezisyonlu olarak gerçekleşmiştir.

Anahtar Kelimeler

• LiDAR
• GPS/RTK
• arama çapı yöntemi
• yatay ve düşey doğruluk

Accuracy Management of LiDAR Data Using GPS Ground Control Points

Öz

Nowadays, both faster and more accurate data acquisition studies are gradually gaining speed, different of traditional land surveying technics in order to obtain land data having high accuration and geometric resolution on mapping. In this study, it is aimed that, to test with RTK/GPS (Real Time Kinematic-Global Positioning System) data of LiDAR (Light Detection and Ranging) Technology, as Remote Sensing Technic, making detection at 1.064nm near infrared region of electromagnetic spectrum in terms of planimetric and vertical accuracy. İn this context, 2x2 km2 forested land, located in Borçka province of Artvin City in the Eastern Black Sea Region of Turkey was selected as study area. In this study, position and elevation differences were estimated between Ground Control Points (GCP) acquired by RTK- and the corresponding LiDAR points, and then, the relationship between the accuracies of these values was tested with search radius method as compared with. Vertical error (RMSEz) was found as 0.20m in normal distribution while it was 0.39 m, vertical accuracy (accuracyz) in 95% confidence interval, Planimetric error (RMSEr) was found as minimum 0.36m, maximum 1.01m, while it was minimum 0.62m, maximum 1.75m planimetric accuracy (accuracyr) in 95% confidence interval. As a result, it was seen that the horizontal error was as twice as the vertical error.

Anahtar Kelimeler

• LiDAR
• GPS (RTK)
• search radius technic
• horizontal and vertical accuracy

Kaynakça

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