5:15 PM - 6:45 PM
[SCG48-P02] An ultralight and compact towed buoy system “Unit-01” for GNSS/A seafloor geodesy
-Aiming for lighter buoy with lower noise-
Keywords:GNSS/A geodesy, Seafloor crustal deformation, Suruga bay, towed buoy
We are developing an ultra-lightweight and compact towed-buoy system for GNSS/A geodetic measurement.
For use in Global Navigation Satellite System-Acoustic ranging combination technique (GNSS-A) geodetic measurement, we developed lightweight, compact towed-buoy system “Unit-00” which can conduct measurement with any vessel (Ikuta et al. 2023; JpGU). The buoy weighs 25 kg and measures 1.3×1.7×0.4 m. It is compact enough to allow attitude measurements using a low-cost gyrocompass to obtain accurate relative position of the GNSS antenna and acoustic TD. It is also light enough to be carried, launched, and retrieved by a few person on board without the use of a crane or winch. We can tow it at a speed close to 7 knots conducting acoustic ranging with sufficient signal-to-noise ratio.
Aiming lighter buoy with lower noise, we developed a new buoy “Unit-01”. Unit-01 weighs 13 kg and measures 0.9×1.7×0.3 m. This is light enough to be carried, launched, and retrieved even by one person on board. Furthermore, the noise level of Unit-01 is approximately 1/3 of Unit-00 when towed at 5knots. We carried out five GNSS-Acoustic measurement campaigns in Suruga bay using these buoys in 2023 (and planning three more campaigns in 2024 before JpGU). The repeated measurements achieved sub-ten centimeter-level seafloor positioning. This buoy system can be an alternative GNSS-Acoustic observation platform that can perform high-quality observations free from dedicated vessels.
<Acknowledgement>
This work was supported by JSPS KAKENHI Grant Number22H01335
For use in Global Navigation Satellite System-Acoustic ranging combination technique (GNSS-A) geodetic measurement, we developed lightweight, compact towed-buoy system “Unit-00” which can conduct measurement with any vessel (Ikuta et al. 2023; JpGU). The buoy weighs 25 kg and measures 1.3×1.7×0.4 m. It is compact enough to allow attitude measurements using a low-cost gyrocompass to obtain accurate relative position of the GNSS antenna and acoustic TD. It is also light enough to be carried, launched, and retrieved by a few person on board without the use of a crane or winch. We can tow it at a speed close to 7 knots conducting acoustic ranging with sufficient signal-to-noise ratio.
Aiming lighter buoy with lower noise, we developed a new buoy “Unit-01”. Unit-01 weighs 13 kg and measures 0.9×1.7×0.3 m. This is light enough to be carried, launched, and retrieved even by one person on board. Furthermore, the noise level of Unit-01 is approximately 1/3 of Unit-00 when towed at 5knots. We carried out five GNSS-Acoustic measurement campaigns in Suruga bay using these buoys in 2023 (and planning three more campaigns in 2024 before JpGU). The repeated measurements achieved sub-ten centimeter-level seafloor positioning. This buoy system can be an alternative GNSS-Acoustic observation platform that can perform high-quality observations free from dedicated vessels.
<Acknowledgement>
This work was supported by JSPS KAKENHI Grant Number22H01335