Gaseous gyroscope

Micro-electromechanical gyroscopes are widely used to in devices as diverse as game controllers and weapons guidance systems. They work by vibrating a tiny mass and then measuring how it is pushed around by Coriolis forces during rotation.

But they have a number of drawbacks, say Lisa Lust and Dan Youngner from the aerospace equipment company Honeywell International in Morristown, New Jersey, US. For example, the devices require highly stable electronics, which are bulky and expensive to make, and are prone to drift as the constituent materials degrade over time.

Lust and Youngner have come up with a new type of gyroscope that avoids these problems. It is essentially a cavity containing a mixture of rubidium and xenon atoms that can be controlled using two lasers.

The first laser causes the gaseous rubidium atoms to become polarised. The rubidium atoms then transfer their spin to the xenon atoms. The second laser can be used to measure the polarisation of the xenon atoms independently of the rubidium.

If the cavity is rotating, the polarisation of the xenon atoms ends up lagging behind the polarisation of the rubidium atoms and the difference gives a straightforward measure of the rate of rotation.

Lust and Youngner say the device is low powered, physically small and robust since it has no moving or vibrating parts. They suggest it could be used to help uncrewed vehicles and robots navigate. Or it could aid personal navigational when GPS is not available – for example, inside a cave or large building.

Read the full atomic gaseous gyroscope patent application.

Justin Mullins, New Scientist consultant