Revolutionary laser technologies pioneered in DARPA’s Defence Sciences Office over the past decades are allowing Air Force researchers to precisely characterise combustion elements in next-generation jet engines and providing commercial gas and oil developers continuous, region-scale monitoring to rapidly detect methane leaks.
The Spectral Combs from UV to THz (SCOUT) programme set out to develop compact, high-precision optical spectroscopy devices to enable rapid detection of multiple trace chemical species in complex environments.
SCOUT researchers were charged with expanding the frequency ranges beyond existing capabilities, reducing the size, improving the performance and shortening the time required to acquire data. Therefore, these devices could be transitioned from bulky, fragile laboratory systems to compact, hardened and robust equipment for field-based spectroscopic applications.
The technology pursued in SCOUT is based on optical frequency combs, comprising thousands of discrete, equally spaced frequency lines that resemble extremely fine teeth on a hair comb. SCOUT researchers achieved many fundamental advances in comb-based spectroscopy, including the development of new materials, physics, and device geometries.
One team from U.S. University further exploited their comb-based spectroscopic system, building a dual-comb spectroscopy device that was ultimately tested in defence and civilian applications. It is transitioning from DARPA to other government activities and the private sector for further development and commercialisation.
SCOUT built upon previous foundational work done in DARPA’s Program in Ultrafast Laser Science and Engineering (PULSE). The results from SCOUT are already paying dividends in applications for the military, other federal agencies, and the commercial industry. The Air Force Research Laboratory (AFRL), for example, is using SCOUT technology for high-speed chemical spectroscopy of complex mixtures, such as combustion materials in ramjet engines, with a precision never before possible.
AFRL has characterised the optical frequency comb system as a leap ahead in the state of the art for laser technology and is now funding the former SCOUT team to further develop the technique for additional diagnostic needs.
With follow-on funding from the Advanced Research Projects Agency–Energy (ARPA-E) and in cooperation with the National Institute of Standards and Technology (NIST), SCOUT researchers spun off an oil and gas monitoring service company, to commercialise a precise long-distance methane detection capability using the frequency combs.
The company offers commercial products to oil and gas companies to detect methane leaks in real-time, which protects the environment by reducing greenhouse gas emissions and improves overall efficiency in the energy production process. The commercialisation of the technology also drives down price, making it more cost-effective for DoD to purchase the devices for defence applications such as ultra-secure communications, high-precision navigation, and extended standoff detection of deadly chemical and biological agents.
The company recently received an additional US$ 5 million from ARPA-E to support scaling its approach for continuous monitoring of methane emissions in oil and gas fields based on the SCOUT technology. A recent test of the company’s system used to identify methane leaks mitigated 43 million cubic feet of methane emissions over 6 months.
In the coming year, the company intends to deploy an additional 25 systems, enabling real-time location and sizing of natural gas emissions across more than 600 square miles of the Permian Basin in the southwestern United States. This will be the largest continuous emissions monitoring network for the oil and gas industry and is projected to reduce oil and gas production emissions by 60%-80% in the region.
DARPA has been encouraging innovation and research in defence technologies. As reported by OpenGov Asia, DARPA invited small businesses to submit innovative research concepts in the technical domains of Electronics, Information Systems. In particular, DARPA was interested in understanding the feasibility of SQUad Intelligent Robotic Radio Enhancing Links (SQUIRREL) and are looking for proposals for small, lightweight, low-power robotic devices.
