Ultrasonic gas monitor developer eyes medical applications

Developed at Cambridgeshire-based TTP, the ultrasonic device - dubbed SonicSense - measures the speed of sound in a gas to determine its composition.

Medical applications include respiratory monitoring, capnography, anaesthesia and COPD monitoring.

Andrew Baker-Campbell, part of the team that developed SonicSense, explained that the simplest application for a medical user would be for mixing different gasses, or monitoring of the mixture of different kinds of gas.

He told The Engineer: ‘In a ventilator, when you’re supporting a patient’s breathing, you might want to mix room air or dry compressed air…with oxygen to give the patient a richer breathing mixture. Controlling the degree of addition oxygen you put in is really important: you don’t want the person to either hyper-or-hypo-ventilate.

‘The measurement essentially says “the speed of sound in the room air is this, the speed of sound of the oxygen is this”, therefore you can plot the speed of sound of a mixture of those two gasses, and by measuring the speed of sound you can infer the composition.’