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Helping engineers see through walls and underground


Dr Gillian Marshall, QinetiQ Fellow

Our world-leading expertise in sensors and test and evaluation is helping to guide the development of a quantum-enabled sensor that will help the planning of high profile, large-scale infrastructure projects and will ultimately enable engineers to see through walls and underground.

Sinkhole shown from New York - helping engineers see through walls and underground

Since the 1980s, researchers have been exploring the possibility of measuring gravity through the quantum superposition: the principle that two or more quantum states can be added together to result in another valid quantum state. Quantum entities can be described as both particles and waves. So by exploiting this concept of wave-particle duality in atoms of rubidium using a laser beam, it is possible to detect very small changes in the way atoms fall freely in a vacuum, determining the local strength of gravity. If the measurement is sensitive enough, it will be able to detect if there are holes, pipes, tunnels and oil and gas reserves in the ground beneath your feet.

QinetiQ is part of a consortium of universities and industrial partners drawn from across the supply chain working collaboratively on a project to develop a quantum-enabled gravity sensor that will help infrastructure planning and works. The project is supported with funding from the Industrial Strategy Challenge Fund (ISCF) quantum pioneer fund, delivered by UK Research and Innovation, and is one of four projects aiming to develop quantum-enabled prototype devices within two years.

As a QinetiQ Fellow, I am part of a community of technical, scientific and engineering leaders within the company who are recognised as national or international experts in our respective fields. Each year, we receive an allowance of 100 hours and £5,000 in order to undertake innovative research, demonstrate thought leadership within expert forums internationally or provide consultancy to consortium-led projects.

This year, I have used some of my Fellows’ allowance of hours – around one day per quarter – to help steer the end-user requirements on the project. Because the consortium comprises university physicists, systems engineers and integrators from industry, equipment or component manufacturers from the whole value chain, through to end users, there has to be a very strong, experienced end user involved and this is where I come in for QinetiQ. Ten years ago, I endeavoured to build gravity sensors so have strong practical experience of the use cases. Being able to shape and guide the overall requirements will be essential for QinetiQ if we are to deliver our expert consultancy services in gravity sensing for this particular project and then on into the future for our customers in defence or critical national infrastructure.

I am particularly interested in the field trial events for the sensors, and I witness them every six months, offering my experience as an end user and making recommendations about how we could do this for real. When a field trial has taken place, and the most recent results are discussed, I am also able to offer my experience to help answer the ‘so what’ question: in other words, the risks involved of taking a piece of kit from the lab to using it in the field. I am able to speak academically to the academics and practically to the engineers and manufacturers. This is the unique skill that QinetiQ offers as a consortium partner: well versed, fluent and confident in the needs of industry and academia and respected and trusted by both as an expert broker.

The first field evaluation established the baseline of what the current equipment can do and how that compares with a commercial (non-quantum) gravity sensor. During the project, we will hold a whole series of field trials to measure the improvements in sensitivity of our gravity sensors and compare it to current equipment. Over the next two years, we will be looking to partners across the supply chain to go from prototype to pre-production towards the production of a commercially available instrument. The manufacturers in our consortium will ultimately be looking to build and sell an instrument, and at QinetiQ, we will be looking to use the instruments for our own test and evaluation to see what can be detected. 

It is extremely important for me to provide input to the project and use my Fellows’ allowance to make a real difference, particularly relating to the future needs of the defence community. If we can get a true up front opportunity now to look at the user experience, we can genuinely shape the process much sooner and much more efficiently, rather than waiting and then not getting what we – and, ultimately, our customers – want.

The main applications of the technology are likely to be detecting sinkholes for brownfield sites, understanding why ballast is being washed away on railway tracks, and identifying unmapped and unknown Victorian culverts and mineworkings. This is a real problem because an estimated 2.5 million roadworks take place in England each year, costing the economy £4 billion in lost working hours and delayed deliveries. Perhaps not surprisingly, large transport and infrastructure organisations are involved in the project and are taking a keen interest in the outcomes of the project. If we can get the sensitivity from the sensors that we hope for, we could detect pipes or possibly even leakages which would be of enormous use for utility companies.

The ability to identify basements and tunnels will also meant that there is an application of the technology for our customers in the defence and law enforcement sectors. As events in Syria have sadly shown, modern conflicts are increasingly fought in highly built up environments: this poses considerable risk to front line or peace-keeping troops who are entering buildings. Equally, experiences in Mexico and Gaza have demonstrated that tunnels are a huge problem across international borders. Applying the technology to keep troops safe by detecting the presence of basements and bunkers, or to identify hidden tunnels which are being used to smuggle people, weapons or drugs for example, would deliver real-world benefit for customers around the world.

It will be in applying this technology that the truly world-class breadth and depth of QinetiQ’s technical expertise will come into its own for customers in defence or critical national infrastructure. We will undoubtedly want to use multiple different-sensors which will mean aligning with our capabilities in multi-modal sensor fusion, signal processing, pattern sensing and machine learning, thus involving several QinetiQ Fellows, who are international experts in these fields.

QinetiQ Fellows excel in consortium-led projects like this. We can use early-stage or experimental technology to test and evaluate the efficacy of the solution, and the level of return on investment, while helping to shape the direction of the technology for end users should the trial be successful. We can leverage our internationally-renowned capability and facilities in test and evaluation to see what we can detect in a variety of environments. Lastly, we can engage with academics and industrial partners with equal fluency. Participating in this technically complex project is thus very interesting, and I look forward to seeing what we learn from the next two years.

UK environmental and engineering firm RSK is leading the project with consortium partners: Teledyne E2V Ltd, Fraunhofer UK Research Limited, UniKLasers, The University of Birmingham and the University of Southampton, as well as Altran, Geomatrix Earth Science, Magnetic Shields, Silicon Microgravity, Optocap and QinetiQ.

Find out more about the 2020 quantum prototype project