By measuring subtle changes (<10-8) in the acceleration of gravity we can infer the local density of nearby objects. When the density is lower (e.g. a tunnel) the local gravity becomes slightly less. While this technique is readily adopted in the oil & gas industry to (i) search for new resources (ii) perform long term monitoring at active wells, broader uptake of gravimetry in other fields is limited due to the high upfront cost of gravimeters ($80k for a Scintrex CG6), the fragility of devices and the time it takes to undertake field surveys with a single instrument. There are disruptive opportunities for gravimetry to breakthrough into other fields including environmental monitoring and security & defence. For environmental monitoring, a smaller-lighter-cheaper gravimeter will open-up opportunities for (i) deployment of sensors arrays of volcanos as a technique to image the magma plumbing system and provide resilience against eruptions, (ii) performing rapid field surveys to identify collapsed culverts, sinkholes or underground tunnels. Within the field of Security & Defence there are further opportunities of monitoring ports of entry with underwater sensors, detecting underground tunnels and monitoring compounds. Beyond this, we see opportunities in monitoring dam infrastructure, carbon capture, geothermal engineering detection/monitoring of underground aquifers. Wee-g is a precision MicroElectroMechanicalSensor (MEMS) that has been developed within the Institute for Gravitational Research (University of Glasgow). It is a spin-off from the Gravitational-Wave research activities led by Prof . Hammond. Wee-g is the world's first gravimeter, capable of monitoring the Earth tides; elastic deformations of the Earth caused by the tidal potential of the Moon and Sun. As typical gravity signals are 10-50% of the Earth ides, this is an essential measurement to show devices have sufficient stability and sensitivity. The Wee-g sensor has the potential to be made much cheaper than existing gravimeters, and thus can open-up these new opportunities in Environmental monitoring and Security & Defence. Field trials are underway with partners in both the Environmental and Security & Defence fields. Wee-g Mk I systems are being deployed on Mt Etna as part of a H2020 project (Newton-g) to monitor magma intrusion in volcanoes, and we estimate the TRL is 5. We also have a system being trialled by DSTL for underwater monitoring at a port of entry. We will use this proposal to further develop the Wee-g gravimeter (Mk II system) to put us in a prime position to spinout. We will address some of the challenges found in the Mk I system including temperature sensitivity of the MEMS chip, miniaturisation and temperature stability of the front-end electronics, and removing reliance on evaluation FPGA boards which are liable to be discontinued.

The Quantum Technology Hub in Sensors and Timing, a collaboration between 7 universities, NPL, BGS and industry, will bring disruptive new capability to real world applications with high economic and societal impact to the UK. The unique properties of QT sensors will enable radical innovations in Geophysics, Health Care, Timing Applications and Navigation. Our established industry partnerships bring a focus to our research work that enable sensors to be customised to the needs of each application. The total long term economic impact could amount to ~10% of GDP. Gravity sensors can see beneath the surface of the ground to identify buried structures that result in enormous cost to construction projects ranging from rail infrastructure, or sink holes, to brownfield site developments. Similarly they can identify oil resources and magma flows. To be of practical value, gravity sensors must be able to make rapid measurements in challenging environments. Operation from airborne platforms, such as drones, will greatly reduce the cost of deployment and bring inaccessible locations within reach. Mapping brain activity in patients with dementia or schizophrenia, particularly when they are able to move around and perform tasks which stimulate brain function, will help early diagnosis and speed the development of new treatments. Existing brain imaging systems are large and unwieldy; it is particularly difficult to use them with children where a better understanding of epilepsy or brain injury would be of enormous benefit. The systems we will develop will be used initially for patients moving freely in shielded rooms but will eventually be capable of operation in less specialised environments. A new generation of QT based magnetometers, manufactured in the UK, will enable these advances. Precision timing is essential to many systems that we take for granted, including communications and radar. Ultra-precise oscillators, in a field deployable package, will enable radar systems to identify small slow-moving targets such as drones which are currently difficult to detect, bringing greater safety to airports and other sensitive locations. Our world is highly dependent on precise navigation. Although originally developed for defence, our civil infrastructure is critically reliant on GNSS. The ability to fix one's location underground, underwater, inside buildings or when satellite signals are deliberately disrupted can be greatly enhanced using QT sensing. Making Inertial Navigation Systems more robust and using novel techniques such as gravity map matching will alleviate many of these problems. In order to achieve all this, we will drive advanced physics research aimed at small, low power operation and translate it into engineered packages to bring systems of unparalleled capability within the reach of practical applications. Applied research will bring out their ability to deliver huge societal and economic benefit. By continuing to work with a cohort of industry partners, we will help establish a complete ecosystem for QT exploitation, with global reach but firmly rooted in the UK. These goals can only be met by combining the expertise of scientists and engineers across a broad spectrum of capability. The ability to engineer devices that can be deployed in challenging environments requires contributions from physics electronic engineering and materials science. The design of systems that possess the necessary characteristics for specific applications requires understanding from civil and electronic engineering, neuroscience and a wide range of stakeholders in the supply chain. The outputs from a sensor is of little value without the ability to translate raw data into actionable information: data analysis and AI skills are needed here. The research activities of the hub are designed to connect and develop these skills in a coordinated fashion such that the impact on our economy is accelerated.