James Savage

Irma 5.2 multi-sensor signature prediction model

The Irma synthetic signature prediction code is being developed by the Munitions Directorate of the Air Force Research Laboratory (AFRL/MN) to facilitate the research and development of multi-sensor systems. There are over 130 users within the Department of Defense, NASA, Department of Transportation, academia, and industry. Irma began as a high-resolution, physics-based Infrared (IR) target and background signature model for tactical weapon applications and has grown to include: a laser (or active) channel (1990), improved scene generator to support correlated frame-to-frame imagery (1992), and passive IR/millimeter wave (MMW) channel for a co-registered active/passive IR/MMW model (1994). Irma version 5.0 was released in 2000 and encompassed several upgrades to both the physical models and software; host support was expanded to Windows, Linux, Solaris, and SGI Irix platforms. In 2005, version 5.1 was released after an extensive verification and validation of an upgraded and reengineered active channel. Since 2005, the reengineering effort has focused on the Irma passive channel. Field measurements for the validation effort include the unpolarized data collection. Irma 5.2 is scheduled for release in the summer of 2007. This paper will report the validation test results of the Irma passive models and discuss the new features in Irma 5.2.

Irma 5.1 multisensor signature prediction model

The Irma synthetic signature prediction code is being developed to facilitate the research and development of multisensor systems. Irma was one of the first high resolution Infrared (IR) target and background signature models to be developed for tactical weapon application. Originally developed in 1980 by the Munitions Directorate of the Air Force Research Laboratory (AFRL/MN), the Irma model was used exclusively to generate IR scenes. In 1988, a number of significant upgrades to Irma were initiated including the addition of a laser (or active) channel. This two-channel version was released to the user community in 1990. In 1992, an improved scene generator was incorporated into the Irma model, which supported correlated frame-to-frame imagery. A passive IR/millimeter wave (MMW) code was completed in 1994. This served as the cornerstone for the development of the co-registered active/passive IR/MMW model, Irma 4.0. In 2000, Irma version 5.0 was released which encompassed several upgrades to both the physical models and software. Circular polarization was added to the passive channel and the doppler capability was added to the active MMW channel. In 2002, the multibounce technique was added to the Irma passive channel. In the ladar channel, a user-friendly Ladar Sensor Assistant (LSA) was incorporated which provides capability and flexibility for sensor modeling. Irma 5.0 runs on several platforms including Windows, Linux, Solaris, and SGI Irix. Since 2000, additional capabilities and enhancements have been added to the ladar channel including polarization and speckle effect. Work is still ongoing to add time-jittering model to the ladar channel. A new user interface has been introduced to aid users in the mechanism of scene generation and running the Irma code. The user interface provides a canvas where a user can add and remove objects using mouse clicks to construct a scene. The scene can then be visualized to find the desired sensor position. The synthetic ladar signatures have been validated twice and underwent a third validation test near the end of 04. These capabilities will be integrated into the next release, Irma 5.1, scheduled for completion in the summer of FY05. Irma is currently being used to support a number of civilian and military applications. The Irma user base includes over 130 agencies within the Air Force, Army, Navy, DARPA, NASA, Department of Transportation, academia, and industry. The purpose of this paper is to report the progress of the Irma 5.1 development effort.

Autonomous Black Hawk in Flight: Obstacle Field Navigation and Landing-site Selection on the RASCAL JUH-60A

This paper describes the development and flight test of autonomous obstacle field navigation and safe landing area selection on the U.S. Army Aeroflightdynamics Directorate RASCAL JUH-60A research helicopter. Using laser detection and ranging LADAR as the primary terrain sensor, the autonomous flight system is able to avoid obstacles, including wires, and select safe landing sites. An autonomous integrated landing zone approach profile was developed and validated that integrates cruise flight, low-level terrain flight, and approach to a safe landing spot determined on the fly. Results are presented for a range of sites and conditions. Approximately 750i¾?km of autonomous flight was performed, 230i¾?km of which was at low altitude in mountainous terrain using the obstacle field navigation system. This is the first time a full-scale helicopter has been flown fully autonomously a significant distance in low-level flight over complex terrain, basing its planning solely on sensor data gathered from an onboard sensor. These flights demonstrate tight integration between terrain avoidance, control, and autonomous landing.

Three-dimensional landing zone joint capability technology demonstration

The Three-Dimensional Landing Zone (3D-LZ) Joint Capability Technology Demonstration (JCTD) is a 27-month program to develop an integrated LADAR and FLIR capability upgrade for USAF Combat Search and Rescue HH-60G Pave Hawk helicopters through a retrofit of current Raytheon AN/AAQ-29 turret systems. The 3D-LZ JCTD builds upon a history of technology programs using high-resolution, imaging LADAR to address rotorcraft cruise, approach to landing, landing, and take-off in degraded visual environments with emphasis on brownout, cable warning and obstacle avoidance, and avoidance of controlled flight into terrain. This paper summarizes ladar development, flight test milestones, and plans for a final flight test demonstration and Military Utility Assessment in 2014.

Powered low cost autonomous attack system: cooperative, autonomous, wide-area-search munitions with capability to serve as non-traditional ISR assets in a network-centric environment

The Powered Low Cost Autonomous Attack System (PLOCAAS) is an Air Force Research Laboratory Munitions Directorate Advanced Technology Demonstration program. The PLOCAAS objective is to demonstrate a suite of technologies in an affordable miniature munition to autonomously search, detect, identify, track, attack and destroy ground mobile targets of military interest. PLOCAAS incorporates a solid state LADAR seeker and Autonomous Target Acquisition (ATA) algorithms, miniature turbojet engine, multi-mode warhead, and an integrated INS/GPS into a 36” high lift-to-drag airframe. Together, these technologies provide standoff beyond terminal defenses, wide area search capability, and high probability of target report with low false target attack rate with high load-outs. Four LADAR seeker captive flight tests provided the sequestered data for robust Air Force ATA algorithm performance assessment and non-sequestered data for algorithm development. PLOCAAS has had three successful free-flight tests in which the LADAR seeker and ATA algorithms have detected, acquired, identified, tracked, and engaged ground mobile targets. In addition to summarizing program activities to date, this paper will present requirements and capabilities to be demonstrated in the next phase of PLOCAAS development. This phase’s objective is to demonstrate the military utility of a two-way data-link. The data-link allows Operator-In-The-Loop monitoring and control of miniature, cooperative, wide-area-search munitions and enables them to serve as non-traditional Intelligence, Surveillance, and Reconnaissance (ISR) assets in a network-centric environment.

Radarometer sensor: simultaneous active and passive imaging using a common antenna

The ability to obtain simultaneous active and passive millimeter wave images using a common antenna has numerous DOD as well as commercial applications. Radiometric and radar images are not new, nor are simultaneous passive and active images of a common scene. The feature that is unique to the radarometer concept is simultaneous use of the same antenna by a radar and a radiometer, operating in the same frequency band at a nominal pixel scanning rate of 1,000 per second. The radarometer sensor is capable of operating in both the passive and active modes either individually, in time sequence, or simultaneously. The radarometer uses a common high-speed mechanically scanned antenna aperture capable of generating active and passive millimeter wave images simultaneously. The important feature of the radarometer design that allows simultaneous active and passive operation in the use of an RF diplexer which separates the signals associated with the radar and radiometer modes. The typical frequency separation displacement is 5 GHz, at a nominal operating frequency of 95 GHz. The results of measurements performed on an engineering test unit will be described.

Three-dimensional landing zone ladar

Three-Dimensional Landing Zone (3D-LZ) refers to a series of Air Force Research Laboratory (AFRL) programs to develop high-resolution, imaging ladar to address helicopter approach and landing in degraded visual environments with emphasis on brownout; cable warning and obstacle avoidance; and controlled flight into terrain. Initial efforts adapted ladar systems built for munition seekers, and success led to a the 3D-LZ Joint Capability Technology Demonstration (JCTD) , a 27-month program to develop and demonstrate a ladar subsystem that could be housed with the AN/AAQ-29 FLIR turret flown on US Air Force Combat Search and Rescue (CSAR) HH-60G Pave Hawk helicopters. Following the JCTD flight demonstration, further development focused on reducing size, weight, and power while continuing to refine the real-time geo-referencing, dust rejection, obstacle and cable avoidance, and Helicopter Terrain Awareness and Warning (HTAWS) capability demonstrated under the JCTD. This paper summarizes significant ladar technology development milestones to date, individual LADAR technologies within 3D-LZ, and results of the flight testing.