US: NASA is developing technologies that will allow landing vehicles to automatically identify and navigate to the location of a safe landing site while detecting landing hazards during the final descent to the surface.
Langley Research Center, Hampton, Virginia, has designed three light detection and ranging (LiDAR) sensors that together can provide all the necessary data for achieving safe autonomous precision landing.
One is a three-dimensional active imaging device, referred to as flash LiDAR, for detecting hazardous terrain features and identifying safe landing sites. The second is a Doppler LiDAR instrument for measuring the vehicle velocity and altitude to help land precisely at the chosen site. The third is a high-altitude laser altimeter providing data prior to final approach for correcting the flight trajectory towards the designated landing area.
In conjunction with laser/ LiDAR sensor development at Langley, NASA’s Jet Propulsion Laboratory, Pasadena, California, is developing algorithms or mathematical procedures for analysing the acquired three-dimensional LiDAR maps and determining the most suitable landing site.
The resulting Doppler LiDAR and laser altimeter data are used by the navigation system being developed by NASA Johnson Space Center, Houston, and Charles Draper Laboratory, Cambridge, MA, to control the spacecraft at the identified location.
These technologies have been integrated as part of NASA’s Autonomous Landing and Hazard Avoidance Technology (ALHAT) project and are in the process of being demonstrated in a series of flight tests.
Source: Space Travel