Development of a MEMs gravimeter for drone-based field surveys.

Gravimetry allows us to study sub-surface structures remotely by measuring changes in Earth's surface gravitational field and using this data to infer the density of geological structures. Of its wide range of applications, it is mostly used in the oil and gas exploration industry, volcanology, civil engineering and even archaeological studies. Airborne gravimetry is a vital method of conducting a spatial gravimetric survey in areas which are difficult to access by foot, such as mountains. Generally, sensors are modified for air crafts platforms by installing them on large gimbal systems, or a strap-down gravimeter can be used as a lower-cost alternative. Now, a new MEMs gravimeter called “Wee-g” is enabling the development of a system to deploy the gravimeter on an unmanned aerial vehicle (UAV or drone). Wee-g was first developed with the objective of developing a low-cost MEMS accelerometer for gravimetric use which could be manufactured on a large scale. In 2016, Wee-g was used to measure Earth tides - the elastic deformation of the Earth caused by gravitational fields of the Moon and Sun. Since then, the device electronics have been miniaturised to make the system portable and has been tested at the Campsie Hills just north of Glasgow. Work is underway to build an isolation platform with active stabilisation on which the Wee-g can be mounted to be deployed on a drone which will reduce airborne surveys costs further and allow for more airborne gravimetric surveys to be carried out in remote locations.