5:15 PM - 6:30 PM
[SVC28-P25] A prototype of advanced Multi-GAS for unmanned aircraft systems
Keywords:Multi-GAS, Volcanic gas, Volcanic plume, UAS, Drone
The composition of volcanic gases reflects the temperature and pressure where they exsolved from magma and the chemical equilibrium reactions during their ascent to the surface. A measurement of their composition is essential to understand the supply system of volcanic gases and their fluctuations during the volcanic unrest. In addition to a conventional method of the volcanic gas composition measurement (sampling and wet chemical analysis), in-situ measurement of plume composition using multiple gas sensors (Multi-GAS: Shinohara et al., 2005, JVGR; Aiuppa et al., 2005, GRL) has become possible. A smaller and lighter Multi-GAS has been recently made with minimal gas sensors, batteries, and data loggers. It has been installed on unmanned aircraft systems (UASs, drones) and has operated at volcanoes with limited access to the craters or volcanoes that are inaccessible due to eruptions (Mori et al., 2016, EPS; Rüdiger et al., 2018, AMT; Stix et al., 2018, JGR; Liu et al., 2018, G-cubed).
In Multi-GAS measurements, the sensor detects changes in the concentration of each component relative to the surrounding atmosphere, and the composition is calculated by the concentration ratio of each component based on the correlation of the concentration changes. It is currently necessary to balance the payload of the drone and the type and accuracy (signal-to-noise ratio) of the onboard gas sensors depending on the situation. At present, it is difficult to measure the main components of volcanic gases comprehensively and accurately with a small drone for general use, and on the other hand, even if a large drone for industrial use can mount high-quality sensors, it is difficult to carry the drone and its peripheral equipment, and the mobility of the drone must be sacrificed to some extent. Therefore, in this study, we have tried to create a lightweight and highly functional drone-borne Multi-GAS that can measure the major components of volcanic gases comprehensively and accurately.
The prototype of drone-borne Multi-GAS (size: L 16 cm × W 21 cm × H 14 cm) consisted of a non-dispersive infrared spectroscopic CO2 sensor and a solid-state H2O sensor (SBA-5, PP Systems, Amesbury, USA), controlled potential electrolysis SO2 and H2S sensors (KTS-512P and KHS 5TA, Komyo Rikagaku Kogyo, Kawasaki, Japan), and a semiconductor H2 sensor (SB-19, Nissha FIS, Osaka, Japan). The analog output of each sensor was recorded to an SD card inside the Multi-GAS by using a microcomputer Lazurite Sub-GHz (LAPIS Technology, Yokohama, Japan; 12 bit AD converter) and a data logging shield for Arduino (Adafruit Industries, New York, USA). The data were also transferred to the pilot in real-time via specified low-power radio communication (920 MHz band). The weight of the Multi-GAS alone was about 600 g, and it is possible to fly safely within the allowable payload of a small industrial drone that can be carried by researchers at volcanoes (e.g., DJI's Matrice 200 V2, 4.69 kg weight with batteries, 1.45 kg maximum payload).
In the future, we will conduct a flight test at an actual volcano to evaluate the measurement accuracy of the new drone-borne Multi-GAS and the data transfer by radio communication. Also, it is necessary to conduct comparative observations with a conventional Multi-GAS to evaluate its performance.
In Multi-GAS measurements, the sensor detects changes in the concentration of each component relative to the surrounding atmosphere, and the composition is calculated by the concentration ratio of each component based on the correlation of the concentration changes. It is currently necessary to balance the payload of the drone and the type and accuracy (signal-to-noise ratio) of the onboard gas sensors depending on the situation. At present, it is difficult to measure the main components of volcanic gases comprehensively and accurately with a small drone for general use, and on the other hand, even if a large drone for industrial use can mount high-quality sensors, it is difficult to carry the drone and its peripheral equipment, and the mobility of the drone must be sacrificed to some extent. Therefore, in this study, we have tried to create a lightweight and highly functional drone-borne Multi-GAS that can measure the major components of volcanic gases comprehensively and accurately.
The prototype of drone-borne Multi-GAS (size: L 16 cm × W 21 cm × H 14 cm) consisted of a non-dispersive infrared spectroscopic CO2 sensor and a solid-state H2O sensor (SBA-5, PP Systems, Amesbury, USA), controlled potential electrolysis SO2 and H2S sensors (KTS-512P and KHS 5TA, Komyo Rikagaku Kogyo, Kawasaki, Japan), and a semiconductor H2 sensor (SB-19, Nissha FIS, Osaka, Japan). The analog output of each sensor was recorded to an SD card inside the Multi-GAS by using a microcomputer Lazurite Sub-GHz (LAPIS Technology, Yokohama, Japan; 12 bit AD converter) and a data logging shield for Arduino (Adafruit Industries, New York, USA). The data were also transferred to the pilot in real-time via specified low-power radio communication (920 MHz band). The weight of the Multi-GAS alone was about 600 g, and it is possible to fly safely within the allowable payload of a small industrial drone that can be carried by researchers at volcanoes (e.g., DJI's Matrice 200 V2, 4.69 kg weight with batteries, 1.45 kg maximum payload).
In the future, we will conduct a flight test at an actual volcano to evaluate the measurement accuracy of the new drone-borne Multi-GAS and the data transfer by radio communication. Also, it is necessary to conduct comparative observations with a conventional Multi-GAS to evaluate its performance.