Robotic Total Station and Analysis of GNSS Measurements

Öz

In this study, the usability of the Robotic Total Station (RTS) and Global Navigation Satellite System (GNSS) measurements in the determination of the relative displacements of the structures were investigated and analyzed with experimental data. For this purpose, two GNSS receiver antennas and Total Station prisma reflectors were installed at the observable height of a high structure in Istanbul. At these two observation points, Real Time GNSS measurements and angle-distance-zenite measurements were performed simultaneously using two RTSs from the monitoring points located at a distance of approximately 580 m. Thus, the time series of these observations were analyzed to determine and compare the amplitude of oscillation of the structure. As a result of the analysis, the following results were obtained; While it was possible to determine the oscillations of 0.5-1 cm amplitude with the centimeter accuracy with GNSS measurements, the oscillations with amplitude with a few mm accuracy (2 mm) with RTS measurements could be recorded but high frequency displacements values ​​could not be determined. These results demonstrated the availability of automated Totalstation systems for the determination of structural displacements as an alternative to GNSS.

Robotik Total Station ve GNSS Ölçümlerinin Analizi

Öz

Bu çalışmada, yapıların bağıl deplasmanlarının belirlenmesinde, Robotik Total Station (RTS) ve Global Navigation Satellite System (GNSS) ölçümlerinin kullanılabilirliği araştırılmış ve deneysel verilerle analiz edilmiştir. Bu amaçla, İstanbul'da bulunan yüksek bir yapının gözlemlenebilir yükseklikte tepesine, iki adet GNSS alıcı anteni ve Total Station prisma reflektörleri monte edilmiştir. Bu iki gözlem noktasında, Gerçek Zamanlı GNSS ölçümleri ve yaklaşık 520 m uzaklıkta bulunan izleme noktalarından iki adet RTS kullanılarak açı-mesafe-zenit öçümleri, eş zamanlı olarak gerçekleştirilmiştir. Böylece, kayıt edilen bu gözlem serileri analiz edilerek yapının salınım genliklerinin belirlenmesi ve karşılaştırılması hedeflenmiştir. Analiz sonucunda şu sonuçlar elde edilmiştir; GNSS ölçümleri ile centimeter doğrulukla 0.5-1 cm genlikli salınımlar belirlemek mümkün olmuşken, RTS ölçümleri ile birkaç mm doğrulukla (2 mm) genlikli salınımlar kayıt edilebilmiş ancak yüksek frekanslı yerdeğiştirme değerleri belirlenememiştir. Bu sonuçlar, otomatize edilen Elektronik Totalstation'ların GNSS’e bir alternatif olarak yapı deplasmanlarının belirlenmesinde kullanılabilirliğini göstermiştir.

Anahtar Kelimeler

• GNSS,Total Station,RTS,Structural Monitoring,Time Series

Kaynakça

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