Development of 3D gas source localization using multi-copter with gas sensor array

Abstract

In this paper, we show experimental studies for three-dimensional gas source localization using a quad-rotor drone with a semiconductor-type gas sensor array. The aerial robots equipped with the gas sensors can be used to detect hazardous chemicals over wide areas. We have been developing the 3D gas drone using a multi-copter, which has the gas sensors mounted directly under each rotor, and the airflow generated by the rotor can be utilized to deliver gases around the drone to the gas sensors. The gas sensor array outputs during both horizontal and vertical movements in the gas plume spread in three-dimensional space was evaluated to estimate the direction of the gas source and gas concentration gradient. The non-causal filtering to realize zero phase lag can be applied to the added and subtracted sensor outputs obtained by two gas sensors mounted under each rotor in the front of the drone. The results show that the combined gas sensor outputs can give the information to estimate the gas concentration gradient corresponding to the gas source direction.