The Naval Undersea Warfare Center Division Newport (NUWC Newport) has developed, tested, and patented a unique beam design to maximize transducer sensitivity to acceleration from a desired direction while minimizing cross axis sensitivity from the orthogonal direction. The crux of the design is a series of lever arm “flappers” inclined at approximately 45 degrees. Vertical acceleration causes the inertial mass of the flappers to bend downward and inward, relieving the strain on the center bridge and the fiber at that position. Connecting a fiber laser to this rigid, low-mass lever arm design enables the fiber laser to experience greater displacement than the center of mass. The result is increasing sensitivity to bandwidth tradeoff.
The innovative lever arm transducer was fabricated from a photopolymer by photolithography for use in 5- and 10-kHz erbium fiber laser sensor designs. Sensitivity at the hundreds of femtostrain level has been achieved. Additional improvements are anticipated with further design modification and material optimization. The sensor device represents an inexpensive approach to high sensitivity on a single axis. Utilizing a second device in a different orientation can create a system that accurately measures movement in both axes. Multiple sensors can be strung together and multiplexed to enable longer devices.
- Highly Sensitive: The innovative lever arm “flappers” have demonstrated sensitivity at the hundreds of femtostrain level with the potential for even better performance with further design and material modifications
- Simple, Inexpensive Manufacturing: Created from polymers via photolithography
- Durable and Cost-Effective: Design has low power consumption requirements and is able to operate in high vibration environments
- US Patents: 7,661,313; 7,802,474 are available for license and commercialization