The Not So Simple SIIMON

SwRI designs, tests and delivers a hand-held biometrics collection kit

Errol M. Brigance     image of PDF button

Photo of Errol Brigance

Errol M. Brigance is a program manager in the Electromechanical and Optical Systems Department of SwRI’s Applied Physics Division. He has expertise in design and construction of mechanical and electromechanical systems, with additional expertise in systems engineering that allows him to integrate RAM functions, such as reliability analysis and prediction, into designs.

photo of System for Intelligence and Identity Management OperatioNs (SIIMON)

The System for Intelligence and Identity Management OperatioNs (SIIMON) allows warfighters to quickly capture iris images, mug shots and fingerprints and compare them to a database or watch list.

image of blue boxes  
photo of the second-generation SIIMON unit

The second-generation SIIMON unit combines a 2.0 megapixel digital camera for mug shot capture, an iris capture camera with infrared LED illumination and a 500 dpi fingerprint reader (below), with a large viewing screen and control panel on the back. The handheld unit replaces a first-generation device that weighed 13 pounds.

photo fingerprint reader  
photo of SIIMON being subjected to environmental testing

To ensure field reliability, SIIMON’s robust structure was subjected to environmental testing conducted at SwRI, including simulations of blowing dust (at left), blowing rain (at right) and harsh maritime environments.

In spy movies, iris scanning, digital fingerprints and voice recognition systems are common high-tech features used to gain entry into high-security areas to obtain data from a protected resource. Biometrics is the study of automated recognition systems that use unique behavioral or physical traits to identify an individual.

In late 2008, Southwest Research Institute (SwRI) was contracted by the U.S. Navy to rapidly develop a light-weight, handheld biometrics collection capability that could be deployed in a harsh maritime environment. The capability needed to be designed, prototyped and tested within six months to meet the Navy’s schedule. The System for Intelligence and Identity Management OperatioNs (SIIMON) was born.


SwRI’s experience in biometrics ranges from hardware design and manufacturing to unique sensor research and development. Since 2006, SwRI engineers have worked on several contracts for the U.S. Navy to develop a hand- held biometrics collection kit. They designed, tested, manufactured and delivered three successive variations of this kit to the client. The first iteration, termed the Tactical Biometrics Collection and Matching System (TBCMS), was developed under a rapid development and deployment initiative. Some key requirements for TBCMS were that it be able to quickly collect fingerprint images, iris scans and facial images of persons of interest in austere environments, such as on board a ship at sea with potential hostiles aboard. In less than a year, SwRI researchers and engineers designed, tested and manufactured this capability to meet the government’s requirements. Initially, a market survey of existing commercial-off-the-shelf (COTS) biometrics sensors and systems was conducted to determine the state-of-the-art products at that time. One of the key performance parameters for TBCMS was that it be rugged enough to withstand MIL-STD-810F and MIL-STD-461E environmental suitability testing.

The market survey showed no systems were available that would inherently meet these testing requirements. SwRI engineers developed several concept designs for this rugged, hand-held collection kit. A formal design review process led to the selection of one design for manufacture. Three test articles were fabricated and were used to successfully complete the MIL-STD environmental testing. Eight prototypes were built and delivered for limited field evaluation. It is important to note that prior to the TBCMS system, users were gathering biometric information using a cluster of commercially available sensors that together weighed more than 75 pounds, were carried in two backpacks, were not ruggedized to handle environmental situations such as being shipboard, and required two persons and at least an hour to set up. The system developed by SwRI performed all of the same functions as the system in use but the Institute significantly decreased the weight from 75 to 13 pounds, created a product that could withstand harsh environments and simplified the process so that only a single person was needed for setup and operation.

Because of the success of TBCMS, SwRI was awarded a follow-on contract with the Navy to further enhance the capability and provide the warfighter with an even smaller, lighter and more robust system. SIIMON (the System for Intelligence and Identity Management OperatioNs) was the successor.


SwRI engineers researched COTS biometrics sensors for collecting fingerprints, iris images and facial images. An original equipment manufacturer’s iris and facial cameras were selected based on their size, weight and ability to be integrated quickly into a custom package. The fingerprint reader selected was the only FBI-certified single fingerprint reader available at the time. The SwRI team selected an ultra-mobile computer that had been tested to MIL-STD-810 and MIL-STD-461 for environmental suitability and could be easily integrated with a multitude of electronics devices. The team quickly designed a rugged housing package to protect the sensors from the anticipated maritime environment, and that provided a robust human-machine interface.

Several rapid prototype models were built to test form, fit and function. After integration testing, injection-molded housings for production were fabricated. The first three units were evaluated in SwRI’s environmental test lab in accordance with MIL-STD-810F, including high and low temperature operation and storage, humidity, blowing rain, blowing dust, solar radiation, salt fog, vibration and transit drop environments.

SwRI’s capability to trim system size with TBCMS was proven by reducing the 75-pound two- pack biometric system that was developed into a trim, 13-pound system that could be set up and operated by one person. SwRI went a step further in designing SIIMON, which weighs only four pounds and can be carried in one hand, allowing warfighters to quickly capture iris images, mug shots, and fingerprints for comparison to a criminal database or watch list. Within seconds, SIIMON provides “detain or pass through” information about a person.

Also for the SIIMON effort, the SwRI team performed a manufacturability study to determine the optimum process for large-scale production. As with TBCMS, the system provided the warfighter with a portable hand-held capability to collect and store fingerprints, iris scans, and facial images. It also allowed the user to search collected data against pre-loaded “watchlists” of up to 100,000 persons of interest. SIIMON also passed rigorous MIL-STD-810F and -461E environmental suitability tests. Six SIIMON systems were delivered for user evaluation.

SwRI provided additional support through another follow-on program titled SIIMON Block II. For this effort SwRI upgraded the biometrics sensors in the SIIMON design and added a larger solid-state hard drive. SIIMON Block II also provided an opportunity to upgrade the system based on field testing and evaluation.

Sensor development

In the midst of the TBCMS and SIIMON efforts, SwRI engineers began developing a unique optical scanner for collecting flat and rolled fingerprints. There are many variations of optical finger scanners in the commercial marketplace, but all are bulky and heavy – most weigh more than 5 pounds. These attributes make them difficult to integrate with a mobile, hand-held capability. “Slap-and-roll” fingerprints, however, are critical pieces of data since they provide arguably the best and most widely used biometric identifiers in the world. Nearly all optical fingerprint scanners use a large glass prism as the sensing surface. This prism occupies a large volume and makes up approximately 80 percent of the weight of the scanner. SwRI optical engineers discovered a way to eliminate the large glass prism, thereby significantly reducing its size and weight. Initial prototypes of the scanner weigh in at only one pound. Development and further refinement are still underway, but so far SwRI has shown that this device can provide users a much-needed mobile capability.

Future developments

SwRI is also investigating the collection of biometrics from stand-off distances. Currently, fingerprint and iris images require that the sensor be either in contact with the subject or less than a foot away. SwRI investigators have shown the ability to capture a cooperative subject’s iris image from as far away as 30 feet with sufficient quality to meet published standards for iris collection. Laboratory experiments have shown that this can be done with optical systems that are approaching hand-held sizes and can provide the required near-infrared illumination of the subject’s eye.

With these capabilities and those already incorporated into SIIMON, Hollywood’s science-fiction toolkits are making the jump off of the screen and into the hands of real-life screeners.

Questions about this article? Contact Brigance at (210) 522-5071 or e-mail

Benefiting government, industry and the public through innovative science and technology
Southwest Research Institute® (SwRI®), headquartered in San Antonio, Texas, is a multidisciplinary, independent, nonprofit, applied engineering and physical sciences research and development organization with 9 technical divisions.