Demonstration for Autonomous Rendezvous Technology
| DART | |
|---|---|
|
|
| Type: | Technology testing satellite |
| Country: |
 United States
|
| Operator: | NASA |
| COSPAR-ID : | 2005-014A |
| Mission dates | |
| Dimensions: | 360 kg |
| Begin: | April 15, 2005, 17:26 UTC |
| Starting place: | Vandenberg / Point Arguello WADZ |
| Launcher: | Pegasus-XL HAPS F-36 |
| Status: | burned up on May 7, 2016 |
| Orbit data | |
| Rotation time : | 96.1 min |
| Orbit inclination : | 96.6 ° |
| Apogee height : | 747 km |
| Perigee height : | 395 km |
Demonstration for Autonomous Rendezvous Technology ( English for demonstrator for autonomous docking systems ), DART for short , was a project funded by NASA . The aim was to develop automatic navigation and docking systems and to test them using the military satellite MUBLCOM . The satellite should approach the target satellite fully automatically. To perform this operation, DART had laser rangefinders and a camera, the data of which it used to calculate the approach course.
The DART satellite was built, launched and operated by the US company Orbital Sciences Corporation . DART was launched on April 15, 2005 with a Pegasus XL rocket dropped from an L-1011 over the Point Arguello Western Air Drop Zone . DART approached its target as planned, but consumed more fuel than planned and canceled the mission, which was planned for a duration of 24 hours, after 11 hours.
On May 15, 2006, NASA published an investigation report into the failed DART mission. It announced that the satellite was first approaching its rendezvous partner MUBLCOM, a military satellite of undisclosed function, also operated by Orbital Sciences Corporation, as planned. Switching from GPS navigation to a video sensor also took place without any problems, although more fuel than planned had already been used at this point. As intended, the video sensor only provided directional information for the target satellite. Distance and position data should only be transferred later. However, this did not take place because the software performed a reset due to the large discrepancy between the measured and planned data. After the reset, the GPS receiver was in operation again, but it was relatively imprecise and could not provide the control with exact data. This led to repeated resets of the control software at intervals of three minutes, between which the control tried to reconcile the measured and planned position by igniting the thrusters. A system started to prevent a collision, but due to the inadequate data it was unable to prevent the two satellites from colliding. This pushed MUBLCOM into a slightly higher orbit, but suffered no damage and was operational again after a system restart.
DART then detected that the fuel supply was almost exhausted, initiated the predicted retreat maneuver and used the remaining fuel to lower the orbit and thus shorten the time spent in orbit. On May 7, 2016, DART burned up when it reentered the earth's atmosphere.
The project cost $ 110 million.
The XSS 11 satellite, developed at the same time by the US Air Force , had a similar task to DART .
Web links
- NASA page on DART (English)
- Overview of the DART Mishap Investigation Results (PDF; 89 kB )
- Raumfahrer.net - Difficult steps into the future
Individual evidence
- ↑ DART in the Encyclopedia Astronautica , accessed on April 24, 2012 (English).
- ^ The Aerospace Corporation: DART. (No longer available online.) In: Upcoming and Recent Reentries. Archived from the original on June 16, 2016 ; accessed on May 19, 2016 (English).
- ↑ Overview of the DART Mishap Investigation Results. (PDF; 89 kB) NASA, May 15, 2006, p. 2 , accessed on April 24, 2012 (English).