SSDW 2005

Results Pictures

With the return of Prof. Ernst Messerschmid to the University of Stuttgart, the Space Station Design Workshop was re-organised, integrated into the summer semester 2005 and supported by a lecture series on Astronautics and Space Station Design. The true SSDW 2005 therefore took place in Stuttgart from 16 June to 7 July 2005.

Two competing teams of students of Aerospace Engineering and Architecture were tasked with the development of a “Geostationary Workshop”, a manned space station in geostationary orbit allowing for satellite servicing as well as for testing of systems and subsystems and long-duration space missions with respect to future exploration in cis-lunar space and on the Moon. The results include top-level system budget data, configuration drawings and models, and simulation data. A public presentation on 7 July 2005 concluded the workshop.

irs2005_group_picture

The SSDW 2005 was unique in its approach of a semester-integrated design workshop for the students in Stuttgart, giving them long teamwork phases to fully exploit the capabilities of the SSDW software tools with support from SSDW staff when needed. However, it has to be considered that the students participated to the workshop in “extra” time while still visiting their other lectures and obligations in their respective study fields.

It has therefore been decided that the upcoming SSDW 2006 will be a full-time one week event as in earlier years. The advantages of this approach are obvious in the full commitment of the participants to the workshop task and human spaceflight in general during the workshop week. It also enables the possibilities of international participation since arrangements with other European institutions and for accomodation of external participants is much less complicated.

Results

This SSDW 2005 was integrated concurrently within the normal aerospace engineering lecture programme, therefore the students had a timeframe of about three weeks for the design development, simulation, and evaluation. This new concept was supported by a lecture series on Astronautics and Space Station Design.

Considering the current roadmaps of the major space-faring nations and following the evolution of the SSDW software the task for this workshop went beyond low Earth orbit: the students had to develop a so-called Geostationary Servicing Workshop (GSW) as a European-Russian lead international venture, starting operation no later than 2014 and serving as precursor for a later station project in the Lunar Libration Point 1. The GSW should primarily demonstrate safe transportation and system development capability using the envisioned infrastructure elements, but it should also enable servicing missions to satellites in GEO as well as research activities in the high Earth orbit environment (phase I). In particular, the station concept should:

  1. be a cost-effective minimum configuration
  2. support human-tended operation with crewed missions twice per year
  3. foresee an international crew of three astronauts
  4. be adapted to extended crewed periods for long-duration and isolation studies, starting around 2016 (phase II)

The students used a modified SSDW methodology, and SSDW tools like COMET, IRIS++ and ELISSA, to design and analyze their stations.

Here is some data on the space station concepts that the two design teams proposed. More detailed information on the workshop and its results can be found in the Final Report (PDF, ca. 5 MBytes).

Blue Team

System Concept:

  • Crew: 3
  • Orbit: geostationary +/- 300 km, circular, 0° inclination
  • Flight mode: earth-oriented
  • Mass in orbit: 60.249 t (phase I), 92.850 t (phase II)
  • Installed electrical power: 58.4 kW
  • Vehicles:
    • transport: Automatic Transfer Vehicle Logistic (ATV-L), Automatic Transfer Vehicle Heavy Duty (ATV-HD) and External Tank Module (ETM)
    • crew transfer: Soyuz-based Crew Rescue Vehicle (CRV)
    • logistics: Progress-based Lunar Transfer Vehicle (LTV)

Space Segment Description:

stationblue_phase1 station_blue

In phase I the station consists of:

  • Service Module (SM, Zvezda-derived)
  • Crew Shelter and Airlock Module (SAM)
  • Advanced Maintenance and Servicing Robot (AMSR)
  • Solar Power Platform (SPP)

In phase II the configuration is adapted:

  • SAM/AMSR are repositioned as above
  • Advanced Habitation Module (AHM) is added

ECLSS Design and Simulation:

In phase I Team Blue anticipated a semi-closed life support system with air revitalisation and waste water recycling. It is designed to support three astronauts for at least 100 days. Major ECLSS components:

  • Water loop: Vapor Phase Catalytic Ammonia Removal Unit (VPCAR)
  • Air loop: Four-Bed Molecular Sieves (4BMS), Electrolysis; Trace Contaminant Control System (TCCS), Sabatier

In phase II the system is further closed by inclusion of biological components for long-term studies. These additions are.

  • an algae Photo-Bio-Reactor (PBR) for air-revitalisation and food production
  • a Salad Machine as a plant growth facility, also for food production
  • an Air Evaporation System (AES) for additional water treatment

Green Team

System Concept:

  • Crew: 3 (6 for short periods in phase II)
  • Orbit: geostationary between 35783 – 35803 km, 0° inclination
  • Flight mode: sun-oriented (inertial)
  • Mass in orbit: 52.870 t (phase I), 77.930 t (phase II)
  • Installed electrical power: 49.47 kW
  • Vehicles:
    • transport: Automatic Transfer Vehicle Logistic (ATV-L), Automatic Transfer Vehicle Heavy Duty (ATV-HD) and External Tank Module (ETM)
    • crew transfer: Soyuz-based Crew Rescue Vehicle (CRV)
    • logistics: Progress-based Lunar Transfer Vehicle (LTV)

Space Segment Description:

In phase I the station consist of:

  • Command and Satellite Service module (COM, Zvezda-derived)
  • Habitation and Laboratory module (LAB, Zvezda-derived)
  • Cupola for observation
  • European Servicing Satellite (ESSAT)

In phase II the configuration is completed by adding:

  • Long Duration Module (LDM)
  • Advanced European Robotic Arm (A-ERA)

This LDM provides additional research facilities as well as an exposed platform.

The ECLSS is a semi-closed system in phase I, enhanced with biological components for further closure in phase II.

station_green

AOCS Design and Simulation:

Due to the positioning of the station in geostationary orbit the forces and torques acting as disturbances are rather small compared to LEO and the solar pressure becomes more relevant. Taking these favourable conditions into account, the station showed excellent attitude performance since the small torques can be easily compensated.

The station uses gyros for accumulation of angular momentum and thruster systems for periodical desaturation manoeuvres (about every 25 days). The figure below shows the simulation carried out using the IRIS++ software for the inertially oriented station of Team Green.

AOCS_simulation
Accumulated angular momentum on all three axes over five orbits

Pictures

Not available yet