A central nervous system for composite materials
30 January 2013
The ability to embed sensors within a material gives engineers scope to measure intrinsic strain of components during their production, or use, under varying load conditions.

Embedded fibre
Building a sensor network within a component or structure that is akin to the human central nervous system, makes it possible to measure loads at almost any position or in any environment. This makes certain demands on the sensing fibre, not least of which is its small size. In response, the draw tower gratings (DTG) specialist, FBGS has introduced its finest DTG fibre yet, measuring just 80µm in diameter.
The new fibre offers some exciting opportunities compared to standard 125µm DTG fibres. Because the fiber is thinner:
- it is less invasive when embedded within laminate composite structures or textiles;
- it requires less force to strain it which makes it more suited for acoustic sensors and hydrophones and
- because it is more 'elastic' in respect to its bending properties, it can be used in applications where small bend radii are required.
The fibre has been released as a beta-product for the 1,550nm window and is drawn with an Ormocer coating that brings the outer fibre diameter to about 114µm.
The new 80µm diameter fiber retains all the attributes of the larger 125 µm DTG product, including:
- extremely high mechanical strength
- spliceless FBG chains
- low bending loss (high NA fiber)
- wide temperature range (cryogenic to +200degC)
- Ormocer coating
- Uniform coating even at FBG position
CEO Hugo Mertens says “this development has come mainly as a result of market forces. The composite and textile industry is very exciting and manufacturers in this sector are starting to incorporate DTG’s for sensing applications. We are simply responding to requests for a fibre that is less invasive to the host material and at 80µm it is all but invisible”.
FBGS would like to build collaborations with those companies that share this vision for 'smart materials'. If you are interested, contact the company at info@fbgs.com or visit the website.