Deployment Mechanisms

RUAG provides several types of passive or active driven mechanisms for antenna, solar array and payload deployment:...

Eddy Current Damper

  • Mass: 750 g
  • Damping Rate: max limit is 1,500 Nm.sec/rad - min limit is 600 Nm.sec/rad.
  • Maximum Torque: 79 +/-5%
  • Max Allowable Start-up Torque: 1.2 Nm
  • Temperature: cold operation temperature of -55 °C

Viscous Deployment Damper

  • Mass: 230 g
  • Deployment Angle: 90° nominal (270° on request)
  • Overall Flange Diameter: 63 mm
  • Overall Length: 81 mm
  • Housing Diameter: 50 mm
  • Working fluid: Silicone Oil Baysilone M 100000 (typical)
  • Damper Characteristics (other values selectable):
    -30 °C: 1,43 x10 3 Nms/rad
    +25 °C: 337 Nms/rad
    +50 °C: 212 Nms/rad
  • Resistive torque: 0.09 Nm (=Break-away torque)
  • Temperature range survival: -150 °C / +150 °C
  • Temperature range operation: -30 °C/+50 °C
  • Leak rate: space environment 3 x 10-9 g/s
  • Life time in space: 15 years

Deployment Mechanism for Large Appendage

RUAG Space has developed and qualified a spring driven, non-reversible Deployment System for Large Appendages, which is focusing on high position accuracy and stiffness in the deployed configuration. In addition, it also provides an integrated deployment damper to eliminate the end position latching shock.

This Deployment System is intended for the deployment of large appendages such as large Reflector Antennas or Solar Arrays.

  • Locking mechanism to provide high position accuracy and stiffness in the deployed configuration
  • Angular contact ball bearing in O-arrangement
  • Dimensions: 122 mm x 110 mm x 70 mm
  • Mass: 1500 g
  • Deployment range: up to 180°
  • Torque: 4 Nm - 10 Nm
  • Stiffness:
    • axial stiffness 1,7 x 107 N/m
    • min. radial stiffness 2,7 x 104 Nm/Rad
    • axial rotation stiffness 2,3 x 104 Nm/Rad (up to 6,1 x 104 Nm/Rad)
  • Resistive Torque: 0,2 Nm
  • Temperature range survival: -150 °C / +150 °C
  • Temperature range operation: -30 °C / +50 °C

Sealed Brush Gear Motor

The Sealed Brush Gear Motor (SBGM) is mainly dedicated as in orbit motion control and actuation mechanism for solar array panels. But the SBGM can also be used for other applications where a robust, simple and space qualified actuator is needed. The SBGM mechanism can be operated in motor and generator (brake) mode. No complex electronic controller is needed.

Rotary Actuators for Antenna Deployment and Pointing Mechanisms

RUAG Space’s Satellite Antenna Rotary Actuators are designed to drive any type of space borne antenna reflectors either connected via a bracket by our customers to a dual or several rotational axis mechanisms or are implemented in RUAG Space’s high reliable Antenna Deployment and Pointing assemblies. The main function of this mechanisms is to precisely fine point antennas in orbit in forward or reverse direction to optimise the antenna view filed to enhance bandwidth, while sending the position feedback to the respective drive electronics. Typical uses of RUAG’s Rotary Actuators include apart from antenna pointing, solar array deployment and customized applications as well. The large range of applications on satellites either in LEO, MEO and GEO orbit for Earth Observation, Scientific or telecommunications purposes, allows using our standard product to minimise costs at system level, having high reliable and robust products.




Mass (kg)

Mission / Application


0.00625 °


Spacebus, SmallGeo


0.0021 °




0.015 °