Since the invention of nuclear power, there have been numerous “accidents.” From Three Mile Island and Chernobyl to the more recent problems in Fukushima, it would seem nuclear power is not fully under our control. Recently a Chinese scientist has warned that the single mountain under which North Korea most likely conducted its five most recent nuclear bomb tests, including the latest and most powerful could be at risk of collapsing. Wang Naiyan, the former chairman of the China Nuclear Society and senior researcher on China’s nuclear weapons program, said that if Wen’s findings were reliable, there was a risk of a major environmental disaster. Another test might cause the whole mountain to cave in on itself, leaving only a hole from which radiation could escape and drift across the region, including China, he said.
One of thrust areas of DARPA is to counter CBRNE threats by developing and testing networked, mobile and cost-effective nuclear- and radiological-weapons detectors that can easily be deployed to provide real-time surveillance over city-scale areas.
Beginning in 2014, DARPA’s SIGMA programme has demonstrated a city-scale capability to detect radiological and nuclear threats, and it is now being operationally deployed. DARPA launched the SIGMA program designed to investigate new technologies that have the potential to protect city-and metropolitan-sized areas from radiological and nuclear-based terror threats through large-scale deployment of low-cost, high-capability radiation sensors and automated detection algorithms to provide real-time alerts of potential threats.
SIGMA program has successfully created high quality, handheld radiological sensors—the size of an average smart phone—at a fraction the cost of today’s devices. SIGMA developed not only that hardware but also the software to monitor thousands of those mobile detectors in real time—an essential capability to discern the movement of nuclear materials before they can be incorporated into a terrorist’s weapon.
Key components of the SIGMA system include small and large form-factor mobile and static radiation sensors intended to support agile deployment strategies; the network infrastructure to connect thousands (up to ten thousand) of these sensors; the cloud-computing infrastructure to automatically analyze streaming spectroscopic data from these sensors in real-time as well as store—in an easily retrievable manner—many billions of these spectra for spatiotemporal and forensic analyses. In addition, the sensors retain local detection capabilities in the event of a network outage. Lastly, these sensors are inventoried, managed, and displayed to analysts to reveal individual and collective device status and sensor output. DARPA has achieved these core components and their integration into the SIGMA system.
Also, DARPA is now looking at expanding SIGMA’s capabilities to include threat detection for other harmful elements such as chemicals, explosives, and biological and radiological agents. DARPA launched SIGMA+ program in 2018 with aim to expand SIGMA’s advance capability to detect illicit radioactive and nuclear materials by developing new sensors and networks that would alert authorities to chemical, biological, and explosives threats as well. “The goal of SIGMA+ is to develop and demonstrate a real-time, persistent CBRNE early detection system by leveraging advances in sensing, data fusion, analytics, and social and behavioral modeling to address a spectrum of threats,” said Vincent Tang, SIGMA+ program manager in DARPA’s Defense Sciences Office.
In April 2018, DARPA’s performer teams partnered with the Indianapolis Metropolitan Police Department, Indianapolis Motor Speedway, and the Marion County Health Department to deploy the network on-site at the Indianapolis Motor Speedway.
“With this network, we’re able to use just the chemical sensor outputs and wind measurements to look at chemical threat dynamics in real time, how those chemical threats evolve over time, and threat concentration as it might move throughout an area.”
DARPA’s SIGMA program developed and tested low-cost, high-efficiency, radiation sensors
A key element of SIGMA, which began in 2014, has been to develop and test low-cost, high-efficiency, radiation sensors that detect gamma and neutron radiation. The detectors, which do not themselves emit radiation, are networked via smartphones to provide city, state, and federal officials real-time awareness of potential nuclear and radiological threats such as dirty bombs, which combine conventional explosives and radioactive material to increase their disruptive potential. Next steps in the SIGMA program include continuing to test full city- and regional-scale, continuous wide-area monitoring capability in 2017 and then transition the operational system to local, state, and federal entities in 2018.
U.S. ‘s Defense Advanced Research Projects Agency (DARPA) had asked industry to design a pocket-sized radiation detector to help foil terrorists attempting to detonate concealed dirty bombs or full-blown nuclear weapons in or around U.S. cities and crucial government and industrial infrastructure. Direct measurement of gamma and neutron emission remains one of the few definitive to detect and identify special nuclear materials and radiological sources, DARPA officials say.
Needed are belt-worn, pocket-size, wearable, and large-area radiation detectors that represent an order of magnitude less expensive with substantially increased detection capability than what is available today, researchers say. DARPA is interested in new packaged dual-mode gamma and neutron detector concepts with an order of magnitude reduction in cost per unit while achieving 5 x and 10 x greater sensitivity in gamma and neutron detection, respectively, compared to the state-of-the art.
For gamma detection, spectroscopy is required, whereas for neutron detection, counting is sufficient. The user interface is expected to be provided by a user-owned mobile device with both USB and wireless secure connection options, and the detector is expected to be worn (e.g., on a belt or in pocket), not held.
SIGMA developed and networked thousands of high-capability, low-cost detectors to demonstrate large-scale, continuously streaming physical sensor networks for the RN interdiction mission. In collaboration with officials in the Washington, D.C., metropolitan area and the Port Authority of New York and New Jersey, DARPA in 2016 tested the devices and networking system at critical transportation hubs and on a city-wide scale involving 1,000 detectors. That test showed the system could fuse the data provided by all those sensors to create minute-to-minute situational awareness of nuclear threats. Working in close cooperation with the Department of Homeland Security, DARPA’s technology has been on track for deployment in multiple locations. SIGMA capabilities have been tested and operationalized with federal, state, and international partners.
Existing Data Ingestion, Streaming Analysis, Storage and Situational Awareness Network Products and Services
In order to plan appropriate follow-on efforts, DARPA is interested in any software products and network infrastructure that may have demonstrated capabilities similar to the SIGMA system.
Invincea Labs, LLC leads these networking and integration efforts within the SIGMA program.
- Ability to ingest, analyze, and store data for thousands (up to ten thousand) spectroscopic sensors reporting full spectral data and device status at 1 Hz, via ~kilobyte sized compressed and encrypted packages transmitted directly through wifi, cellular, or other communication means to a cloud-based network backbone;
- Ability for bidirectional communication with these sensors;
- Ability to run multiple computationally-intensive detection, identification, tracking and sensor fusion algorithms in real-time with minimal reporting latency (~seconds);
- Ability to manage inventory and device status (including sensor health, calibration data and other metadata) for many thousands of heterogeneous sensors;
- Ability to display and report device status, sensor output, and location in real-time to analysts and commanders through web-based Command and Control (C2) interface designed for thousands (up to ten thousand) sensors, providing real-time threat monitoring, situational awareness, and blue-force tracking capability;
- Ability to query recent historical data (~month) with minimal latency (~10-100 ms);
- Storage of multiple years of sensors data (~10 TB/year);
- Ability to simulate many thousands of sensors to demonstrate scalability and to replay historical sensor data through the system for multiple purposes, including for example testing of new algorithms or development of new concepts-of-operation;
- Security and encryption appropriate for national security information systems (e.g., NIST 800-53);
- Ability to deploy on multiple commercial cloud infrastructures (e.g., Amazon Web Services (AWS), Azure) or locally on premise;
- Ability to support expansion into novel sensor modalities, detection algorithms, and data fusion;
- Code base with unlimited rights.
DARPA is also more generally interested in production and operational grade software and Internet of Things (IoT) development organizations with expertise (or planned expertise) in the following areas:
- Massive sensor networks reporting in real-time;
- Advanced data analytics with very stringent performance guarantees;
- Familiarity with the challenges presented by heterogeneous sensor physics and sensor fusion approaches;
- Unique security and privacy concerns inherent in a distributed national-security system, including cybersecurity requirements.
Kromek to support DARPA’s SIGMA dirty bomb detection programme
UK-based radiation detection company Kromek has secured two separate contracts from the US Department of Defense (DoD) to support the Defense Advanced Research Projects Agency’s (DARPA) SIGMA programme. Valued at $6m, the deal requires the company to supply spectroscopic personal radiation detectors (D3S) in support of the programme.
The SIGMA programme aims to develop an advanced personal detection system for gamma and neutron radiation that can be combined with other such systems to form large networks to detect radiation signatures over an extended area. The technology used could provide early warning about acts of terrorism such as a ‘dirty bomb’. The second contract, which is valued at $0.75m, covers the supply of 12,000 inductive charging packs for D3S detectors and associated mobile devices. The inductive charging pack provides a long battery life for the detectors, and can be recharged and recalibrated when necessary.
Kromek CEO Arnab Basu said: “The D3S is the world’s first fully approved combined gamma and neutron detector available in volume shipment and at a market leading unit price of $400, which is also available to other user organisations buying over 10,000 detectors in a single procurement.
SIGMA+ or SIGMA Enhancements
While the SIGMA program was initially developed to detect nuclear and radiological threats, the overall SIGMA concept (distributed networked sensors with automated threat detection) is compatible with providing early warning of many other types of WMT threats; the existing SIGMA system is flexible enough to support multiple operational concepts and deployment scenarios.
DARPA is therefore interested in existing products and services, and new research and development efforts, to extend and enhance the capabilities of the SIGMA system. These enhancements may involve improvements to detection power, system robustness, alert reliability, inclusion of novel sensor types and modalities (e.g., sensors for chemical or biological threats or contextual sensors such as cameras with analytics informing threat detection events), sensor and intelligence fusion concepts, or other approaches coherent with and enabling to the existing SIGMA capability and SIGMA’s overall counter-terror mission.
SIGMA+ calls for the development of highly sensitive detectors and advanced intelligence analytics to detect minute traces of various substances related to weapons of mass destruction (WMD) threats. SIGMA+ will use a common network infrastructure and mobile sensing strategy, a concept that was proven effective in the SIGMA program. The SIGMA+ chemical, biological, radiological, nuclear and high-yield explosive (CBRNE) detection network would be scalable to cover a major metropolitan city and its surrounding region. Planned execution of SIGMA+ will occur in two phases. Phase 1 will focus on developing novel sensors for chemicals, explosives, and biological agents while Phase 2 will focus on network development, analytics and integration.
As part of this study, DARPA researchers from MIT Lincoln Laboratory, Physical Sciences, and Two Six Labs, built a small network of chemical sensor packages. Using the chemical sensor network and the data collected during the events, the team was able to assess the performance of the sensors and network algorithms. DARPA Defense Sciences Office programme manager Anne Fischer said: “The algorithms were developed using a custom simulation engine that fuses multiple detector inputs. We built the algorithms based on simulant releases in a large metropolitan area – so we took existing data to build the algorithms for this network framework.
In April 2018, DARPA’s performer teams partnered with the Indianapolis Metropolitan Police Department, Indianapolis Motor Speedway, and the Marion County Health Department to deploy the network on-site at the Indianapolis Motor Speedway. DARPA researchers could also collect a large relevant data set and user feedback that will assist ongoing system development efforts.
At present, the agency is advancing additional sensor modalities, including short-range point sensors to extend the capabilities for networked chemical detection. Fischer added: “We’re looking at how we might make this network more robust and more mature.” “For example, we implemented a network at Dugway Proving Ground as part of a DoD test for simulant releases, and have shown that the network can respond to a number of chemical simulant threats different than those used in Indianapolis, as well as built-in capabilities for mobile releases.”
These systems will further be developed and integrated into the SIGMA+ continuous, real-time, and scalable network architecture to increase the capabilities of the system to monitor chemical and explosive threats.
Silverside Detectors working with Onshape to make Nuclear radiation Sensors
Silverside Detectors, a Massachusetts-based company specializing in nuclear security, is using tools from Onshape, a cloud-based CAD software provider. The objective is to develop low-cost compact-sized nuclear radiation detectors. Philip Taber, Silverside VP of Hardware Engineering, praised the efficiency of Onshape software, “We switched to Onshape because we urgently needed help with data management.”
Program Manager and Applied Physicist at DARPA, Dr. Vincent Tang, states, “The SIGMA program aims to revolutionize detection and deterrent capabilities for countering nuclear terrorism.” Tang further elaborates, “A key component of SIGMA thus involves developing novel approaches to achieve low-cost, high-efficiency, packaged radiation detectors with spectroscopic gamma and neutron sensing capability.”
Nuclear radiation detection
Helium-3 is an isotope of the helium gas. It is non-radioactive and is used in the detection of nuclear radiation. In recent years, due to the increased threat of nuclear terrorism, the demand of helium-3 has peaked, which has resulted in a shortage of the isotope. In 2001, the demand of helium-3 was 8,000 liters per year, whereas in 2008 it went up to 80,000 liters/year, decreasing the accumulated stockpile of the isotope.
One way to counter this problem is using elements other than the helium-3 and developing smaller radiation sensors. Silverside Detectors, working on the SIGMA program and partly funded by DARPA, has a solution. The company wants to build a lithium-based (Li-6) neutron detectors, which is compact in size and cost-effective.
Leveraging 3D technology
Now, Onshape with its 3D software capabilities will help Silverside Detectors speed up the development of the Li-6 nuclear radiation detector. Jon Hirschtick, CEO of Onshape further added, “Silverside Detectors is genuinely making the world a much safer place … We’re proud that Onshape is playing a role in speeding up the production of their nuclear radiation detectors and getting them deployed on the ground as quickly as possible.” “Onshape probably cuts our design time in half because we’re designing our parts together in one place versus flipping back and forth between files. We can make changes without worrying about breaking the assembly.”
SIGMA+ Network and Analytics Proposers Day
The Defense Sciences Office is holding a Proposers Day meeting and webcast to provide information to potential proposers on the objectives of the SIGMA+ program’s Network and Analytics thrust area. SIGMA+ will develop a persistent, real-time, early detection system for the full spectrum of chemical, biological, radiological, nuclear, and explosives (CBRNE) WMD threats at the city-to-region scale. The Network and Analytics thrust will pursue developments for automated, large-scale intelligence and data analytics for the SIGMA+ system, further developments for the SIGMA network backbone that are expected to be required to perform full fusion of these data and methods, and interface and interoperability.