Autonomous communicating sensor networks developed to monitor aircraft structures

October 30, 2013 // By Julien Happich
The StrainWISE project, initiated by Airbus as part of the “Clean Sky” program, resulted in the development of a high-performance and ultra-low-power wireless sensor network platform able to monitor aircraft critical structures.

Developed in cooperation with Imperial College and CSEM, the self-powered wireless communication devices open up new possibilities for the preventive maintenance of aircraft, for improving cabin supervision and passenger comfort, as well as for better monitoring aircraft critical structures and equipment such as engines or landing gear.

The proposed solution, which won the top prize in the “Research” category at the Mechatronics Awards 2013, allows the installation of a large number of sensors, without any restrictions on their location, hence providing additional or more precise data. The new information, provided without any additional wiring, allows for an improved control of the aircraft and presents major advantages compared to traditional solutions, notably in terms of fuel consumption and maintenance costs.

Each sensor is equipped with a radio transceiver and an independent power supply. Energy consumption, both during flight and while the aircraft is on the ground, has been reduced to a minimum by a combination of energy-efficient electronic components and by the optimisation of the communication protocol.

The sensor is powered by energy harvesting from a thermoelectric unit, removing the need to change batteries throughout the sensor’s 35-year life. Thanks to this autonomy, a wide array of sensors can now be placed very close to the structures to be monitored, at places that would be very difficult to access for maintenance, such as in the fuselage, the wings and the stabiliser. Each sensing node allows the measurements to be timed with an accuracy of less than a millisecond, for sampling frequencies ranging from 120 to 500 Hz. The information is communicated to the aircraft's computers by RF link. They do not interfere with the operation of the pre-existing devices, as the system successfully passed the qualification tests related to radio interference.

A demonstrator has been delivered to Airbus and is currently undergoing tests. The partners are pursuing their collaboration as part of a new Clean Sky project called “FLITE-WISE”, the objective