Posted on 07/13/2002 12:39:22 PM PDT by Dallas
MOSCOW, July 13 (UPI) -- Russian space officials still are looking for the Demonstrator-2 inflatable space vehicle that was launched Friday from a nuclear submarine in the Barents Sea, the TVS television network reported Saturday.
The vehicle was supposed to land on the Kura training ground on the remote Kamchatka Peninsula on Russia's Pacific coast. Earlier, Babakin Space Center spokeswoman Lidia Avdeyeva confirmed the landing, but efforts to locate the vehicle so far have failed to bear fruit, TVS reported.
Officials from Russia's Mission Control were unavailable for comment Saturday.
On Friday, Russia's Ryazan nuclear sub launched Demonstrator-2 on a converted Volna SS-N-18 intercontinental ballistic missile. The launch took place at 4:58 a.m. Moscow time, Russian Navy spokesman Igor Dygalo told reporters.
The vehicle, developed jointly by the Babakin Center, the European Space Agency and the German-based Astrium space firm, aims to revolutionize cargo deliveries and transportation of astronauts. According to designs, Demonstrator-2 will be used for carrying payloads to space stations and returning crews to Earth. Russian designers also are contemplating using the vehicle for exploration missions to other planets.
Last week, Russian space officials called on their colleagues worldwide to launch a joint effort to explore Mars.
Demonstrator-2 is small in size -- the folded-up vehicle measures less than 3 feet in diameter making it the most compact space vehicle ever made. However, its ability to inflate two thermo-proof panels it carries to up to 13 feet provides for aerodynamic breaking, which can reduce the craft's speed by nearly a thousand times.
Before landing, the vehicle can slow to a speed of about 45 feet per second -- 30 miles an hour -- ensuring a survivable impact with the landing surface.
Two previous attempts to launch Demonstrator-2 ended in failures. Two years ago, the craft's panels failed to inflate to their maximum size as the vehicle carried equipment from a space mission and eventually became lost. Then, in July 2001, it carried to space a solar sail developed by the Babakin Center, but failed to gain enough thrust during the third stage of the launch, preventing separation of the spacecraft from the booster rocket.
Copyright © 2002 United Press International
Under contract of ESA and the European Community the German Astrium GmbH is presently preparing the second test flight (Inflatable Rentry and Descent Technology IRDT-2) for the demonstration of a novel reentry technology making use of an inflatable aerobraking shield. The project conducted jointly with the Babakin Space Center, Moscow, aims at the development of a download system for the International Space Station, which is able to return small payloads to the ground independent of the US Space Shuttle. IRDT makes use of technologies originally developed within the Russian Mars program and differs from common recovery systems for reentry capsules or sounding rockets. Instead of a parachute an inflatable heat shield is employed to decelerate the capsule and land it safely on ground.
The IRDT-2 capsule will be launched by a Volna rocket from a Kalmar type submarine in the Baltic sea north of Murmansk and injected into a ballistic trajectory passing across the arctic sea and northern Siberia (Fig. 1). Following deployment of the first shield, the capsule reaches the rentry point at a 100km altitude and a velocity of roughly 7 km/s. Here, a second shield is deployed which introduces a steep descent of the capsule. The actual landing takes place on the Kamshatka peninsula within 25 min after separation.
As part of the IRDT-2 payload, a modified Orion GPS receiver for space applications will be flown by DLR/GSOC and the resulting navigation data will complement other sensors and experiments in the post mission analysis. In view of the short mission duration and the fact, that the IRDT unit will only be switched on at separation from the upper stage, special precautions have to be taken to allow for a hot start of the GPS receiver at boot time even under the high dynamics of the re-entry trajectory. The Mitel Orion receiver has therefore been selected for the IRTD tracking system, since it supports software modifications through the Mitel Architect development system.
The receiver and interface board measure 95 x 50 mm each and are stacked on top of each other inside the housing shown in Fig. 2. The power consumption of the complete GPS unit amounts to roughly 3W. The standard Mitel firmware has received numerous changes to improve the tracking performance under highly dynamical conditions and to allow a fast acquisition of the receiver. This include updates of various receiver parameters (operational limits, filter parameters) as well as fixes of the Doppler computation and the kinematic navigation solution for fast moving host vehicles. Also, a small time offset that would otherwise introduce a measurable along track error in space applications has been corrected in DLR's receiver software.
A major modification concerns the use of a position-velocity aiding concept, which makes use of a piece-wise polynomial approximation of the nominal flight. Based on this, the reference position and velocity of the vehicle in the WGS84 reference frame are computed approximately once per second. The result is then used to obtain the line-of-sight velocity and Doppler frequency shift for each visible satellite, which in turn serve as initial values for the steering of the delay and frequency locked loops. For use on IRDT-2, the polynomials are referred to the instant of separation from the launcher, which coincides with the boot time of the receiver.
Inflatable Re-Entry Shield Now Tested In Space
Solar-Sail project of the Planetary Society (Cosmos-1)
Montenbruck O., Markgraf M., Leung S.;
Ein GPS Empfänger für Raumfahrtanwendungen ;
Deutscher Luft- und Raumfahrtkongress 2001 der DGLR, Hamburg 17.-20. Sept. (2001).
Montenbruck O., Markgraf M., Leung S., Gill E.;
A GPS Receiver for Space Applications;
B1-Ax; ION GPS 2001 Conference, Salt Lake City, 12-14 Sept. 2001 (2001).
Someone is going to be job hunting soon.
a.cricket
Kind of recalls the M.O.O.S.E.
--Boris
Found it!
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.