Self Powered wireless sensors for HUMS in Aeronautical Applications

Distributed health and usage monitoring

Health and usage monitoring systems (HUMS) are used in aircraft to monitor, for example, engine and gearbox performance by collecting and analysing data from a range of sensors. At the moment, wired sensors are widely used but their installation and maintenance costs are extremely high.

Batteries, as the primary power supply for wireless sensors, have a limited lifetime and consequential maintenance issues. By harvesting power from the environment, this issue is removed, so wireless sensors can offer the opportunity for simple deployment, and also for embedded deployment, with the sensors being an integral part of the fabric of the aircraft. Recent work at Southampton in the EU FP7 project, TRIADE, has demonstrated the viability of powering intelligent sensors from ambient vibration. This has resulted in a credit card-sized self-powered sensor demonstrator.

Technological advantages of self-powered wireless sensors

• Easy deployment and ideal for retrofit on existing aircrafts
• Fit-and-forget feature
• Embedded intelligent sensors
• Long lifetime power solution
• Low maintenance cost

Technology Roadmap
Two alternative technologies have been developed. A credit card sized (85×55×3 mm) wireless sensor node, powered by a piezoelectric energy harvester, was demonstrated under vibrations taken from a helicopter, resulting in the generation of 240 µW (3m/s ² at 67Hz). Such energy allows the node to transmit measured data over the Zigbee network every 10 minutes.

A low profile electromagnetic energy harvester was also developed. It has dimensions of 55×55×3 mm and has the smallest thickness among all reported non-MEMS electromagnetic energy harvesters. This achieves high-energy density within a planar structure. The harvester generates 450 µW of power when excited under the same vibrations from a helicopter.

Collaboration opportunity

The University of Southampton has over 15 years of experience in developing kinetic energy harvesters, as well as self-powered wireless sensors. Self-powered systems developed at Southampton have already been used in practical applications on trains and ferries. Opportunities exist for developing the technology for specific applications.

If you would like to know more, please contact Dr Nick Harris nrh@ecs.soton.ac.uk