Line-Distributed Hoop Strain Sensor Navy SBIR FY2011.3 Sol No.: Navy SBIR FY2011.3 Topic No.: N113-180 Topic Title: Line-Distributed Hoop Strain Sensor Proposal No.: N113-180-0102 Firm: SA Photonics, LLC 130 Knowles Drive Suite A Los Gatos, California 95032 Contact: Jim Coward Phone: (415) 977-0553 Web Site: www.saphotonics.com Abstract: Vibrations of large objects can cause structural fatigue, cracks and even collapse. Therefore, it is important to monitor the vibrations of large valuable structures to ensure structural integrity. Current hoop strain sensing systems use a large number of point sensors such as accelerometers or fiber Bragg Gratings. These systems are complex, difficult to install, have high maintenance and require significant signal processing. Therefore, easy to install and low maintenance hoop strain sensing systems capable of measuring average circumference strain with very high sensitivity and dynamic range are needed. SA Photonics technologies have enabled the construction of high performance hoop-strain-sensing systems. SA Photonics will construct the system using our RIS, ND and SBE technologies. The hoop-strain-sensing system will have sensitivity down to nano-Epsilon and dynamic range over 80 dB. It will operate under wide temperature ranges, insensitive to vibration and EM interference. It will also be rugged and easy to install. Benefits: SA Photonics will use our RIS, ND and SBE technologies to construct a high performance hoop-strain-sensing system that can measure the average strain of the circumference of a large structure. There are multiple benefits to the NAVY: - Very high strain sensitivity: < nano-Epsilon - Very high dynamic range: > 80 dB - Frequency range: dc to > 1 KHz - Simple signal processing - Operate under wide environmental conditions: temperature: -10 to 80C ; humidity: 0 to 100%; insensitive to vibrations and sounds; and immune to EM interference - Easy installation, turn-key operation and close to no maintenance required Return