In TRIADE, industrial specifications will require a Health and Usage Monitoring System (HUMS) performing Structural Health Monitoring (SHM) functions during flights which must exhibit a very high level of autonomy. The power consumption will be minimised to achieve the best use of the energy obtained from the battery and energy-harvesting units, which will be subjected to very stringent space limits. Within TRIADE, the following applications will be considered: - To explore the 'out-of-flight domain' conditions and/or to monitor the integrity and health of parts and structures, which have been repaired in the field; - To increase the efficiency of aircraft maintenance. The inspection of completed or ongoing EU projects shows that these goals cannot be achieved in aeronautics today with the non-intrusiveness, autonomy, size and cost requirements.
The following technical outputs differentiate TRIADE from other EU projects, particularly the ADVICE project: - Fully depleted Silicon on Insulator (SOI) CMOS technology targeted for Ultra Low Power (ULP) functions, sensors and interfaces. Breakthrough solutions will also have to be developed to bring embedded neural network intelligence. The overall TRIADE objective is to contribute towards solving application issues by providing technology building blocks and fully integrated prototypes to achieve power generation, power conservation and embedded powerful intelligence- data processing/storage and energy management for structural health-monitoring sensing devices in aeronautical applications. - Include a neural tool and data processing in the prototype, which will fulfil the power consumption requirements; -Validate the robustness of the solution to an aeronautic environment.
Technical development will result in a disposable smart tag that includes a battery, an antenna, an RF inductive coupling link, a memory, an energy-harvesting part, a power management circuit and a microprocessor. Remote sensors will be connected to the tag: a humidity sensor, one or two XY strain gauges, an acceleration sensor, and ULP temperature and pressure sensors. This tag will be stuck in the last layer of the composite (with a lifetime of at least ten years), or on the structure (lifetime of six months to one year). The project is divided into six technical work packages (WP).
WP1 is essentially concerned with HUMS environmental and functional requirements, overall architecture and interfaces with low power in mind. WP2 will deal with peripheral components. In particular, this WP will be concerned with the adaptation of peripheral components to the aeronautics requirements: energy-harvesting sources and batteries. Several interfaces will be implemented: RF link, microprocessor, power interface between energy source and batteries, remote sensors implemented with low power solutions.
WP3 will be aimed at upgrading and establishing the SOI CMOS/MEMS platform for embedded electronics and sensors. Selected critical functions will be developed with ULP concepts. WP4 will focus on studying the embodiment of the electronics, how it adapts to processes and process temperature, environmental and service life. Simulations for structural integrity assessment will be performed and transferred for use in WP6.
WP5 consists of neural network computation. It will focus on developing a software-computing tool, compatible with previous requirements and choices. WP6 is concerned with the development of a prototype to be put on a small technological specimen containing fasteners: stuck on the specimen, the prototype will be tested with an environmental cycle defined by the end-users. The major deliverable of the project will be the HUMS smart tag device that could be stuck on the structure or in the last layer of the composite of an aircraft in order to record the external parameters, e.
g. temperature, pressure, moisture and vibrations. The smart tag will respect the compatibility with the manufacturing processes and service life. It will be the size of a credit card so as to be easily used in the aeronautics domain and allows for further monitoring applications.
Several other technological results with breakthrough building blocks will be issued from this smart tag: - SOI-based ultra-low power components. The expected impact of TRIADE is its contribution to reducing aircraft operating costs by 50%, through a reduction in maintenance/inspection and other direct operating costs by 2020. Before TRIADE, smart maintenance systems were not embeddable on board aircraft; after TRIADE, smart systems will be embeddable. Before TRIADE, smart maintenance systems consumed 250 mAh and lasted a few hours when continuously powered; after TRIADE, they consume 30 mAh and may be used intermittently for ten years.