Intensity based interrogation of optical fibre sensors for industrial automation and intrusion detection systems

Author

Gary Andrew Allwood, Edith Cowan UniversityFollow

Date of Award

2015

Document Type

Thesis

Publisher

Edith Cowan University

Degree Name

Doctor of Philosophy

School

School of Engineering

Faculty

Faculty of Health, Engineering and Science

First Supervisor

Associate Professor Steven Hinckley

Second Supervisor

Dr Graham Wild

Abstract

In this study, the use of optical fibre sensors for intrusion detection and industrial automation systems has been demonstrated, with a particular focus on low cost, intensity-based, interrogation techniques. The use of optical fibre sensors for intrusion detection systems to secure residential, commercial, and industrial premises against potential security breaches has been extensively reviewed in this thesis. Fibre Bragg grating (FBG) sensing is one form of optical fibre sensing that has been underutilised in applications such as in-ground, in-fence, and window and door monitoring, and addressing that opportunity has been a major goal of this thesis. Both security and industrial sensor systems must include some centralised intelligence (electronic controller) and ideally both automation and security sensor systems would be controlled and monitored by the same centralised system. Optical fibre sensor systems that could be used for either application have been designed, developed, and tested in this study, and optoelectronic interfaces for integrating these sensors with electronic controllers have been demonstrated. The versatility of FBG sensors means that they are also ideal for certain mainstream industrial applications.

Two novel transducers have been developed in this work; a highly sensitive low pressure FBG diaphragm transducer and a FBG load cell transducer. Both have been designed to allow interrogation of the optical signal could occur within the housing of the individual sensors themselves. This is achieved in a simple and low cost manner that enables the output of the transducers to be easily connected to standard electronic controllers, such as programmable logic controllers. Furthermore, some of the nonlinear characteristics of FBG sensors have been explored with the aim of developing transducers that are inherently decoupled from strain and temperature interference. One of the major advantages of optical fibre sensors is their ability to be both time division and wavelength division multiplexed. The intensity-based interrogation techniques used here complement this attribute and are a major consideration when developing the transducers and optoelectronic circuits. A time division multiplexing technique, using transmit-reflect detection and incorporating a dual bus, has also been developed. This system architecture enables all the different optical fibre transducers on the network to have the same Bragg wavelength and hence the number of spare replacement transducers required is minimal. Moreover, sensors can be replaced in an online control system without disrupting the network. In addition, by analysing both the transmitted and reflected signals, problems associated with optical power fluctuations are eliminated and the intensity of the sensor signals is increased through differential amplification.

Overall, the research addresses the limitations of conventional electrical sensors, such as susceptibility to corrosive damage in wet and corrosive environments, and risk of causing an explosion in hazardous environments, as well as the limitations of current stand-alone optical fibre sensor systems. This thesis supports more alert, reliable, affordable, and coordinated, control and monitoring systems in an on-line environment.

Related Publications

Allwood, G., Wild, G., Lubansky, A., & Hinckley, S. (2015). A highly sensitive fiber Bragg grating diaphragm pressure transducer. Optical Fiber Technology, 25, 25-32. doi:10.1016/j.yofte.2015.06.001. Link to article available here.

Allwood, G., Wild, G., & Hinckley, S. (2015). Optical Fiber Sensors in Physical Intrusion Detection Systems: A Review. IEEE Sensors Journal, 16(14), 5497 - 5509. doi: 10.1109/JSEN.2016.2535465. Link to article available here.

Allwood, Wild, & Hinckley (2013). Optical fiber Bragg grating based intrusion detection systems for homeland security. Paper presented at the Proceedings of the 2013 IEEE Sensor Applications Symposium (SAS 2013). doi: 10.1109/SAS.2013.6493558. Article available here.

Allwood, Wild, & Hinckley (2012). A comparison of InGaAs and Ge photonic power converters for long wavelength power-over-fibre. Paper presented at the Proceedings of the Conference on Optoelectronic and Microelectronic Materials and Devices (COMMAD 2012). doi: 10.1109/COMMAD.2012.6472337 Link to article available here.

Allwood, Wild, & Hinckley (2012). Wavelength division multiplexing of a fibre Bragg grating sensor using transmit-reflect detection system. Paper presented at the Proceedings of the 37th Australian Conference on Optical Fibre Technology (ACOFT 2012). Article available here.

Allwood, Wild, & Hinckley (2012). In-Ground Optical Fibre Bragg Grating Pressure Switch for Security Applications. Paper presented at the Proceedings of the 3rd Asia-Pacfic Optical Sensors Conference 2012 (APOS 2012). Article available here.

Allwood, G., Wild, G., & Hinckley, S. (2011). A comparison of silicon and germanium photovoltaic power converters for power over fibre. Paper presented at the Proceedings of SPIE 8204, Smart Nano-Micro Materials and Devices, 820410 (December 23, 2011); doi:10.1117/12.903294. Link to article available here.

Allwood, G., Wild, G., & Hinckley, S. (2011). Programmable logic controller optical fibre sensor interface module. Paper presented at the Proceeding of SPIE 8204, Smart Nano-Micro Materials and Devices, 82040P (December 23, 2011). doi:10.1117/12.903235. Link to article available here. Available from here.

Allwood, Wild, & Hinckley (2011). Programmable Logic Controller Based Fibre Bragg Grating In-ground Intrusion Detection System. Paper presented at the Proceedings of the 2011 Australian Security Congress (SECAU 2011). Article available here.

Allwood, Wild, & Hinckley (2011). Fibre Optic Acoustic Sensing for Intrusion Detection Systems. Paper presented at the Australian Acoustical Society Conference, Acoustics 2011: Breaking New Ground. Article available here.

Access Note

Access to Chapter 9 of this thesis is not available.

Recommended Citation

Allwood, G. A. (2015). Intensity based interrogation of optical fibre sensors for industrial automation and intrusion detection systems. Edith Cowan University. Retrieved from https://ro.ecu.edu.au/theses/1702