NSF convergence accelerator track L: UAV-assisted dual-comb spectroscopic detection, localization, and quantification of multiple atmospheric trace-gas emissions

The National Science Foundation (NSF) awarded a $650,000 Project Grant under the NSF Technology, Innovation, and Partnerships (CFDA 47.084) program to Princeton University. The grant supports the development of an innovative laser sensing technology platform that will employ dual-comb spectroscopy and quantum cascade laser frequency combs to enable three-dimensional localization and quantification of multiple atmospheric trace gas emissions. The novel chemical sensing system will integrate with lightweight unmanned aerial vehicles to provide rapid, cost-effective monitoring of greenhouse gases, toxic air pollutants, and other volatile compounds over large areas. This project represents convergent research in physics, engineering, applied mathematics, and optics, and will contribute to workforce development across the STEM fields.

Abstract

Detecting chemical gas plumes is important for monitoring air quality. This project addresses the challenging problem of detecting, localizing and quantifying gas emissions and detecting sources. The novel chemical sensing technology developed under this research project will provide a three-dimensional (3D) localization of airborne chemicals, creating maps to address a broad variety of trace-gas sensing applications of high societal importance. Applications include the monitoring of greenhouse gas (e.g. from landfills, wastewater treatment plants, agriculture, or other industries), monitoring of farming environments to enrich yield, measuring exposure to toxic air pollution in communities located near industrial zones, or real-time assessment of disaster zones to provide actionable information to first responders. In addition to the technological and commercial impact, the project represents a unique mixture of fundamental physics, engineering, applied mathematics and optics, and will provide training for students at every level of educational ladder, thus contributing strongly to the development of a diverse and globally competitive stem workforce in the US. To address the challenging problem of detecting, localizing and quantifying gas plumes of multiple volatile chemicals, an innovative laser sensing technology platform that offers 3D spatial concentration mapping is proposed. This technology will employ a novel dual-comb spectroscopic (DCS) sensor system based on chip-scale semiconductor quantum cascade laser frequency combs (QCL-FCS) operating in the mid-infrared molecular fingerprint spectral region. These new lasers sources provide both broadband mid-infrared coverage required for multi-species detection, and ultra?high spectral resolution the enables high chemical selectivity. The QCL-DCS system will be configured into a retroreflector-based optical remote sensing system integrated with novel robotic capabilities provided by lightweight unmanned aerial vehicles (UAVS), and coupled with advanced atmospheric fluid dynamics models to synergistically provide a powerful sensing platform that enables 3D tomographic localization of multiple chemical sources over large areas. Ultimately, the proposed UAV-assisted QCL-DCS sensing platform will be optimized for rapid deployments and will achieve cost-efficiency via scalable semiconductor manufacturing and large deployment footprints, offering qualities that are highly desired in both commercial and government sectors. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the foundation's intellectual merit and broader impacts review criteria.- subawards are planned for this award.