Who is involved in ALHAT?
ALHAT is managed by Johnson Space Center (JSC) in Houston, TX, but the
work is distributed between both NASA and Non-NASA facilities. JSC is also responsible for the real-time computing element, or HAST, that will be the "brain" of the ALHAT system - computing the navigation solution and the TSAR algorithm results. JSC also contributes heavily to the Guidance, Navigation, and Control (GNC) aspects of the system, in conjunction with University of Texas (UT), Charles Stark Draper Labs (CSDL) an Utah State University (USU). Finally, JSC coordinates the Systems Engineering efforts both across the multiple centers and between ALHAT and the Altair project.
JPL is responsible for the Terrain Sensing And Recognition (TSAR)
algorithms and implementing the field tests (FT1 through FT6) to collect data for
testing the developed sensors and algorithms.
Langley Research Center (LaRC) is responsible for terrain sensor hardware development, and thus far that includes an imaging LIDAR, LASER Altimeter, and LASER Doppler Velocimeter. LaRC also provides the POST simulation environment to
test out models of the algorithms and sensors.
The Charles Stark Draper Lab is responsible for integration and testing of the Guidance, Navigation, and Control (GNC) portion of the project, and works with the aforementioned JSC/UT/USU team to produce the GNC system that can use the HDA, TRN, and HRN measurements produced by TSAR within an Altair-derived spacecraft architecture.
The Applied Physics Laboratory (APL) is providing an additional terrain-relative navigation algorithm, called APLNav, and is presently tasked with managing the Verification and Validation portion of the Systems Engineering efforts for the project.
Where are the ALHAT activities performed?
The tasks are split amongst the various centers, with field testing occurring at NASA Dryden Flight Research Center (DFRC), Death Valley National Park, and the Department of Energy (DoE) Nevada Test Site (NTS).
For example, we are concluding the activities for Field Test 3 today, by flying the two remaining flights at 8km above ground level (AGL) at Death Valley this morning, and at the Nevada Test Site (NTS) this afternoon. The team of members from JPL, LaRC, and APL are convened at Nellis Air Force Base with the aircraft to execute the two flights, and then de-integrate our equipment. This test program has collected data over flat, rugged, and cratered terrain using both active and passive sensors. This data will now be processed by our algorithm teams to show performance of Terrain Relative Navigation.