[meteorite-list] Successful Test Flights for Mars Landing Technology (ADAPT)

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?feature=4514

Successful Test Flights for Mars Landing Technology

Fast Facts:

* ADAPT test system can help a spacecraft divert its course and make a 
smooth, pinpoint landing

* Two technology demonstration test flights were completed in California

It's tricky to get a spacecraft to land exactly where you want. That's 
why the area where the Mars rover Curiosity team had targeted to land 
was an ellipse that may seem large, measuring 12 miles by 4 miles (20 
by 7 kilometers).

Engineers at NASA's Jet Propulsion Laboratory in Pasadena, California, 
have been developing cutting-edge technologies that would enable spacecraft 
to land at a specific location on Mars -- or any other planetary body 
-- with more precision than ever before. In collaboration with Masten 
Space Systems in Mojave, California, they have recently tested these technologies 
on board a high-tech demonstration vehicle called the Autonomous Descent 
and Ascent Powered-flight Testbed (ADAPT).

ADAPT is a test system built on Masten's XA-0.1B "Xombie" vertical-launch, 
vertical-landing reusable rocket. The Xombie platform provides a good 
approximation of Mars-like descent conditions through high-speed descent 
rates at low altitudes. Those conditions are difficult to achieve through 
conventional flight test platforms. Onboard this rocket, two sophisticated 
lander technologies were recently tested: Terrain Relative Navigation 
with a sensor called the Lander Vision System (LVS), and the Guidance 
for Fuel-Optimal Large Diverts (G-FOLD) algorithm.

"No previous Mars lander has used onboard surface imaging to achieve a 
safe and precise touchdown, but a future spacecraft could use LVS and 
G-FOLD to first autonomously determine its location and then optimally 
fly to its intended landing site," said Nikolas Trawny, ADAPT's principal 
investigator at JPL. "All of this happens on board, without human intervention, 
and in real time."

ADAPT had two successful test flights, one on Dec. 4, 2014, and the second 
on Dec. 9. In both cases, the rocket reached a maximum altitude of 1,066 
feet (325 meters) before beginning its descent.

The terrain-relative navigation capability provided by LVS allows Xombie 
to precisely determine its position without requiring GPS. To do so, ADAPT 
first takes a series of pictures of the terrain below it during descent. 
These pictures are then compared to an image of the terrain stored onboard, 
allowing the vehicle to autonomously find its position relative to the 
landing site. The spacecraft can then use this information to correct 
its course to get as close to the targeted landing site as possible within 
its capability, and make a smooth, pinpoint landing.

G-FOLD is an algorithm, developed at JPL and at the University of Texas 
at Austin, that calculates the optimal path to divert a spacecraft to 
a target landing site in real time. For the first time, G-FOLD allows 
onboard calculation of divert trajectories that obtain the maximum performance 
from every kilogram of propellant.

The combination of LVS and G-FOLD allowed the Xombie rocket to begin to 
change the course of its descent at about 623 feet (190 meters) in the 
air on December 9. The rocket then flew the newly calculated course to 
successfully reach the target landing pad located 984 feet (300 meters) 
to the east.

"This represents a huge step forward in our future capabilities for safe 
and precise Mars landing, and demonstrates a highly effective approach 
for rapid, low-cost validation of new technologies for the entry, descent 
and landing of spacecraft," said Chad Edwards, chief technologist of the 
Mars Exploration Directorate at JPL. "This same technology has valuable 
applications to landing on the moon, asteroids and other space targets 
of interest."

NASA's Space Technology Mission Directorate is facilitating the tests 
via its Flight Opportunities Program managed at NASA's Armstrong Flight 
Research Center at Edwards Air Force Base, California.

JPL, a division of the California Institute of Technology, Pasadena, manages 
the ADAPT project and funded the ADAPT payload development. The LVS prototype 
was designed, developed and tested by the Mars Technology Development 
program of NASA's Science Mission Directorate.


Media Contact

Elizabeth Landau
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6425
Elizabeth.Landau at jpl.nasa.gov 

2015-091