Captive flight testing (CFT) of sensors and seekers requires accurate data collection and display for sensor performance evaluation. The U.S. Army Redstone Technical Test Center (RTTC), in support of the U.S. Army Edgewood Chemical Biological Center (ECBC), has developed a data collection suite to facilitate airborne test of hyperspectral chemical/biological sensors. The data collection suite combines global positioning system (GPS) tracking, inertial measurement unit (IMU) data, accurate timing streams, and other test scenario information. This data collection suite also contains an advanced real-time display of aircraft and sensor field-of-view information. The latest evolution of this system has been used in support of the Adaptive InfraRed Imaging Spectroradiometer (AIRIS), currently under development by Physical Sciences Incorporated for ECBC. For this test, images from the AIRIS sensor were overlaid on a digitized background of the test area, with latencies of 1 second or less. Detects of surrogate chemicals were displayed and geo-referenced. Video overlay was accurate and reliable. This software suite offers great versatility in the display of imaging sensor data; support of future tests with the AIRIS sensor are planned as the system evolves.
The U.S. Army Redstone Technical Test Center (RTTC) has been supporting captive flight testing of missile sensors and seekers since the 1980's. Successful integration and test of sensors in an airborne environment requires attention to a broad range of disciplines. Data collection requirements drive instrumentation and flight profile configurations, which along with cost and airframe performance factors influence the choice of test aircraft. Installation methods used for instrumentation must take into consideration environmental and airworthiness factors. In addition, integration of test equipment into the aircraft will require an airworthiness release; procedures vary between the government for military aircraft, and the Federal Aviation Administration (FAA) for the use of private, commercial, or experimental aircraft. Sensor mounting methods will depend on the type of sensor being used, both for sensor performance and crew safety concerns. Pilots will require navigation input to permit the execution of accurate and repeatable flight profiles. Some tests may require profiles that are not supported by standard navigation displays, requiring the use of custom hardware/software. Test locations must also be considered in their effect on successful data collection. Restricted airspace may also be required, depending on sensor emissions and flight profiles.
The Airborne Chemical Imaging System (ACIS) is a research platform used to evaluate passive infrared (IR) standoff detectors for airborne remote sensing of chemical vapors. It consists of a sensor suite mounted in an automated gyro-stabilized optical platform. The sensor pod is currently mounted on a UH-1 helicopter but could also be adapted to other platforms. Two developmental IR imaging sensors are used in the ACIS: a high-speed Fourier transform infrared (FTIR) spectrometer: the TurboFT, and a high-resolution tunable IR Fabry-Perot spectroradiometer: the AIRIS. The TurboFT is a high-speed (100 Hz) low-resolution (2x8 pixel) system and the AIRIS is a low-speed (~0.5 Hz), high-resolution (64x64 pixel) imager. This paper describes the ACIS configuration, general system specifications, operational concerns, and some typical results from recent flight tests.
Airborne testing of sensors presents unique challenges to the researcher. Prototype sensors are not typically configured for aircraft mounting, and testing requires comparative (truth) data for accurate sensor performance evaluation. The U.S. Army Redstone Technical Test Center (RTTC) has developed a large Stabilized Electro-optical Airborne Instrumentation Platform (SEAIP) for use with rotary wing aircraft as a sensor test bed. This system is designed to accommodate the rapid integration of multiple sensors into the
gimbal, greatly reducing the time required to enter a sensor into testing. The SEAIP has been designed for use with UH-1 or UH-60 aircraft. It provides nominal 35 μradian (RMS) line-of-sight stabilization in two axes. Design has been optimized for support of multiple/large prototype (brassboard) sensors. Payload combinations up to 80 lbs can be accommodated. Gimbal angle ranges are large to permit flexibility for sensor pointing. Target acquisition may be done manually, or with the use of a GPS tracker. Non-visible
targets may be engaged, and sensor information may be mapped real-time to digitized maps or photographs of the test area. Two SEAIP systems are currently used at RTTC. Numerous sensors have been
successfully integrated and tested, including MMW, LADAR, IR, SAL, multi-spectral, visible, and night vision.