FBG Accelerometers (Pebble Series)

Data Sheet

The Optilab Pebble, a compact and lightweight Fiber Bragg Grating (FBG) based accelerometer, is designed for Oak Creek Fiber Sensing System and is optimized for structural health monitoring (SHM) or machine condition monitoring (CMS) .

Product Overview

The Pebble can be attached to a machine (pump, compressor, generator or rotor ,etc.) Alternatively, Pebble can be incorporated to a structure such as bridge, dam, building, etc. Pebble’s ruggedized sealed metallic body and armored cables allows it to be placed in a wide range of environments. Due to its unique design, the Pebble has a wide operating frequency range while maintaining an high level of sensitivity.


  • Civil, industrial, or Aerospace Health Monitoring (SHM)
  • Condition Systems Monitoring (CMS)
  • Fiber optic sensors and traducers interrogation
  • Laboratory Testing and Measurement
  • R&D


  • Robust, Reliable, Compatible
  • Completely passive
  • High multiplexing capability
  • Remote sensing
  • Self-referenced

Feature Name Description
Sensor Specifications
Sensitivity Polyimide 1.2 pm/με Composite 1.2 pm/με Weldable 1.2 pm/με Surface ST 1.5 pm/με Surface LG 1.2 pm/με Embedded ST 1.5 pm/με Embedded LG 1.2 pm/με
Measurement Range ±2500 με
Gauge Length Polyimide <10 mm Composite 92 mm Weldable 25 mm Surface ST 107 mm Surface LG 1005 mm Embedded ST 104 mm Embedded LG 1002 mm
Resolution 1 με
Optical Specifications
Central Wavelength 1500 to 1600 nm
Spectral Width (FWHM) < 0.2 nm
Reflectivity > 65%
Side Lobe Suppression > 10 dB
Input/Output Specifications
Cable Type Ø 0.9 mm laboratory (hytrel) Ø 3 mm indoor (kevlar) Ø 3 mm outdoor (armor)
Cable Length 2 m each side (±5 cm)
Connectors FC/APC SC/APC NC (No Connectors)
Environmental Specifications
Operation Temperature -20 to 80 ºC
Protection Class Surface IP68 Embedded IP68
Mechanical Specifiations
Materials Polyimide film Composite GFRP and polyurethane Weldable stainless steel Surface stainless steel Embedded stainless steel
Dimensions Polyimide 40 x 12 x 0.2 mm Composite 130 x 20 x 6 mm Weldable 45 x 15 x 0.3 mm Surface ST 163 x 35 x 20 mm Surface LG 1065 x 35 x 20 mm Embedded ST 140 x Ø 30 mm Embedded LG 1040 x Ø 30 mm