Quantum Sensing on the London Underground

Many parts of our society are now heavily reliant on Global Navigation Satellite Systems (GNSS). Not only are they used to facilitate the supply chains that support our economy, they also enable the movement of goods and people in unfamiliar places, they help maintain power networks, and they support our emergency services and military. It has been shown that 8% of UK GDP relies on satellite enabled navigation, and that a five-day outage would cost £5bn. GNSS does not provide a fail-safe system for determining position. It does not work underground or underwater, it is vulnerable to local weather conditions, and it can be spoofed or blocked. This broad economic reliance on GNSS, combined with its vulnerabilities, means the UK increasingly needs to find robust and secure alternatives to satellite navigation.

Because GNSS cannot be relied upon for safety critical positioning on rail networks there is a need for more accurate and reliable positioning systems, particularly on the London Underground. Our team at Imperial College London are developing a new type of hybridised inertial sensor technology that harnesses quantum physics, with the potential to accurately determine position without the need to send or receive signals. In the future trains carrying our quantum enhanced navigation systems may be able to register their position on the network accurately and reliably without the need for significant external infrastructure.

We have partnered with Transport for London (TfL), a key stakeholder in the civilian mass transit sector, to extensively test our new technology on their trains. With 45% of their network underground they have a need for improved positioning technologies in order to increase capacity, offer greater reliability and provide a safer experience for all.

In this project we are going produce a more precise and more stable hybrid inertial sensor, which we will ruggedise and deploy through field trials on the TfL network. This represents a critical step in translating quantum sensors from the laboratory into quantum technologies that can bring about societal benefits.