EpsilonPeak

The first Fibre Bragg Grating (FBG) – EpsilonPeak averaging the structural strains along its base (10 mm as standard) for accurate and repeatable measurements with high sensitivity and range.
 
The unique FBG sensor without spectrum splitting that allows the measurements and control of non-homogenous materials such as Fibre Reinforced Polymers (FRP) or concrete.
There is also a possibility to measure steel in the plastic deformation range (yielding), where strains perpendicular to the optical fibre axis can occur as a result of non-uniform strain field.


Datasheet

EpsilonPeak Advantages

Resistance to spectrum splitting (distortion) caused by non-uniform strain field in a wide strain range
The obtained spectrum does not require additional calculations and simulations because the spectrum is unambiguous
Small size FBG sensor without external casing – can be installed in hard-to-reach, tight places
Easy and repeatable installation thanks to a dedicated set of accessories
Compatible with standard optical fibres and interrogators
Possibility to perform static and dynamic measurements

Physical Quantities Measured

Strain Sensing
Temperature Sensing

Typical Materials

Concrete
Steel
Composite

EpsilonPeak Application Areas

Structures | Bridges | Piles | Dams | Pipelines | Tunnels | Railways | Earthworks | Laboratories… and more

How our FBG sensor works vs. competition

Homogeneous strains along the FBG sensor cause proportional changes in its period (Λ), shifting the spectral peak to shorter or longer wavelengths.

Homogeneous strains along the FBG sensor cause proportional changes in its period (Λ), shifting the spectral peak to shorter or longer wavelengths. However, homogeneous strain are rare in practice. Materials like FRP, concrete, or steel under plastic deformation create non-uniform strain fields, leading to broadened, split, or deformed spectral peaks, making accurate and trusted strain measurements impossible. Our sensor averages these non-uniform strains over the grating length, enhancing measurement range and reliability, similar to electrical foil strain gauges.
Our sensor – EpsilonPeak
Competition
Period in non uniform strain

EpsilonPeak Technical Specifications

Optical properties

Range of available central Bragg wavelengths1

1407-1607 nm

Accuracy of central Bragg wavelength

±50 pm

Full Width at Half Maximum

< 150 pm

Side Lobe Suppression Ratio

15 dB

Type of FBG

uniform/apodised

Fibre outer diameter (excl. coating)

125 μm

Fibre type2

bend-insensitive photosensitive

Sensing properties

Physical length of FBG

1-10 mm

Number of FBGs on one fibre

customised

Strain range3

from ± 4000 to ± 50 000 με

Strain accuracy

not worse than 0.5% of the measurement range

Thermal compensation

external/second FBG

Working temperature

from -30 to +70°C

Fibre termination4

none, bare fibre

Calibration card5

is added to each sensor

1 Exact wavelengths available upon request
² As standard, different types of optical fibres available upon request
3 As standard for bend-insensitive photosensitive fibre. Strain range may differ
for different types of optical fibres
4 As standard, different fibre terminations available upon request
5 Each FBG is carefully checked. Each sensor is supplied with a calibration card
containing an equation that allows the conversion of the central wavelength
into strains

Yielding steel and composite (FBG application examples) and strain map

EpsilonPeak Installation

Each installation should be designed individually, taking into account specific requirements and local conditions. However, there are three typical methods:

Gluing directly onto the surface
Bonding directly to sanded, cleaned and degreased structural surface
Installation during composite production in the infusion and pultrusion proces

EpsilonPeak FAQ

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Datenblatt
Broschüre

Andere Produkte

EpsilonRebar
EpsilonGraph
EpsilonFlat
3DSensor
EpsilonPeak
PDS
SDD

Mehr

Anwendungsbeispiele
Lesen Sie unsere FAQ
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