ESA Document - Emits - ESA

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HMM
Assessment Study
Report: CDF-20(A)
February 2004
page 219 of 422
Advanced rigid arrays have the following features:
• Typically four or five panel wings with surface area of 30-35 m 2 (typical panel size
2.5 m x 2.75 m).
• Spring-driven, single-direction deployment, with latched panels for in-flight wing
stiffness
• No Re-stowed latching capability
Polar platform arrays have the following features:
• Up to 16 panel capability with surface area of 80 m 2 (typical panel size 5 m x 1 m,
current qualification status of 14 panels).
• Motorised, cable actuated deployment with re-stowage capability (not yet qualified).
• No Re-stowed latching capability
The Polar platform type array would better suit this application given the number of.
Additionally, the requirement for re-stowage is better facilitated with a motorized deployment
system.
3.3.8.2.2 Communications system
The following assumptions have been derived as a result of the study:
• All boom-mounted antennas require tracking capability.
• Tracking can be realized with two perpendicular rotational axes.
No trade-off has been performed. The choice of the chosen mechanism has been made based
upon the available systems and the requirements stated earlier.
3.3.8.2.3 Vehicle connections
The following assumptions have been applied:
• Only the DM and ERC require berthing and docking ports
• Further Module assembly in LEO will be performed by Berthing Mechanisms, aided by
LEO facilities i.e. robotic arm capture of module and assisted berthing
• A spare berthing and docking port is required for in-orbit contingency
Two systems have been considered:
1 Russian Docking System
2 International Docking & Berthing Mechanism (IDBM)