The initial aim of this project was to develop a non-contact fibre optic based displacement sensor to operate in the harsh environment of a 'Light Gas Gun' (LGG), which can 'fire' small particles at velocities ranging from 1-8.4 km/s. The LGG is used extensively for research in aerospace to analyze the effects of high speed impacts on materials. Ideally the measurement should be made close to the centre of the impact to minimise corruption of the data from edge effects and survive the impact. A further requirement is that it should operate at a stand-off distance of ~ 8cm. For these reasons we chose to develop a pseudo con-focal intensity sensor, which demonstrated resolution comparable with conventional PVDF sensors combined with high survivability and low cost. A second sensor was developed based on 'Fibre Bragg Gratings' (FBG) which although requiring contact with the target the low weight and very small contact area had minimal effect on the dynamics of the target. The FBG was mounted either on the surface of the target or tangentially between a fixed location. The output signals from the FBG were interrogated in time by a new method. Measurements were made on composite and aluminium plates in the LGG and on low speed drop tests. The particle momentum for the drop tests was chosen to be similar to that of the particles used in the LGG.
|Conference||21st International Conference on Optical Fiber Sensors|
|Period||15/05/11 → 19/05/11|
Poster. Jackson, David A.; Cole, M.J.; Burchell, M.J. and Webb, David J. Fibre optic sensors for high speed hypervelocity impact studies and low velocity drop tests. IN: 21st International Conference on Optical Fiber Sensors (OFS21). Ottawa (CA), 15-19 May 2011, Wojtek J. Bock; Jacques Albert; Xiaoyi Bao (eds.), 231, (2011). 21st International Conference on Optical Fiber Sensors (OFS21), 15-19 May 2011, Ottawa (CA).
Copyright 2011 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.
- non-contact fibre optic based displacement sensor
- harsh environment
- Light Gas Gun
- small particles
- high speed impacts
- pseudo con-focal intensity sensor
- PVDF sensors
- Fibre Bragg Gratings
- particle momentum