document title / titre du document TRP W ORK PLAN ... - emits - ESA

TRP Work Plan 2005-2007
Description of Activities
TEC-SB/7935/dc
12/Feb/09
TRP Reference:
Title:
T603-38EC
Enhanced CCD Star Tracker
Since the introduction of the Autonomous Star Trackers in the 1990s, their popularity and use on space missions has steadily
increased until today were these units are used on all classes of mission and are becoming the sensor of choice for almost all
missions.
The European space industry has been at the forefront of this technology development, indeed in 2000/2001 there were
nearly 15 European companies developing or selling star trackers. This amount of competition was unsustainable and so, at a
harmonisation meeting in 2001, it was decided to no longer support the development of CCD based star trackers and
concentrate instead on targeted developments to produce the next generation of star trackers based on APS detectors, these
having the potential to allow lighter, more compact and cheaper Star Trackers that simultaneously offered higher robustness.
Industry was left to support itself for the CCD star trackers. This policy had the desired effect of reducing the number of
European Star Tracker manufacturers dramatically while simultaneously forcing manufacturers to improve their units and
reduce prices. Today there are 5 star tracker suppliers in Europe, each of whom have survived by being highly competitive on
the world stage. With a manageable number of suppliers, a large proportion of each of these companies business now coming
from outside Europe and there still being an expected overlap of 2 to 4 years between CCD based and APS based star
tracker supply it is now time to resume providing support to maintain and improve the existing CCD based product lines.
The Terma HE-5AS STR has been selected for Cryosat, Aeolus and the LPF missions. Following the loss of Cryosat at launch
it is also expected to fly on Cryosat 2. Work performed now to secure the STR and improve its robustness, reliability and
qualification status will therefore have a near term beneficial effect on several ESA missions.
This policy was clearly expressed in ESA/IPC(2005)70 rev.1, calling for product improvements of CCD Star Tracker , mainly
for recurring platforms. According to the outcomes of the 2005 Harmonisation Roadmap on AOCS Sensors and Actuators, the
present activity aims at: ensuring the availability of the HE-5AS to ESA projects for at least the next 3 years; improving the
robustness and ease of use of the HE-5AS within the scope of the existing electrical design limitations; improving the
straylight and thermal design and the understanding of their interactions and dependencies on the s/c system and orbital
environment. This will result in the following main three tasks: 1. Software improvements for Robustness and Reliability; 2.
Component obsolescence and Europeanisation; 3. System level analysis and improvements. This measure is implemented in
line with IPC(2005)30, rev. 1 (Formal review of the geographical distribution of contracts), calling for a DG's additional effort to
improve the geographical return of certain countries, including Denmark.
Deliverables:
In-flight data analysis report; design improvements and trade off report; improved SW design report; SW Test
plan/procedures/report
Current TRL:
TRL3-4 Target TRL: Application Need/Date: TRL8 (in-flight demo on
TRL5-6
Cryosat-2) by 2009
Application/Mission: All missions Contract Duration: 18 months
T-25, T26, T-27, T-29, T-30,
SW Clause : - Dossier0 Ref.:
T-33, T-34, T-965
Consistency with Harmonisation
Conclusions: ESA/IPC(2005)70 rev.1
Roadmap and Conclusions:
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