CMG-40m Control Moment Gyroscope

The CMG-40m is an evolution of the CMG-10m and consists of four variable speed, single-gimbal Control Moment Gyroscope (CMG), specifically tailored for 12U and 16U CubeSats. Unlike traditional CMGs driven by two or three motors, one single CMG is driven by only one spherical motor, making it capable of minimizing into a CubeSat form factor. Serving as an attitude actuator component, the CMG-40m can provide Torque and Speed modes through commands from the user’s onboard computer (OBC) or ADCS computer. 

Furthermore, the CMG-40m has been designed to fit within the so-called “tuna can” of CubeSat structures, minimizing its volume within the satellite and enabling larger payload missions. 

The user’s control system design can be simplified by adopting the torque mode, but it requires a tumbling rate of < 1 deg/second. The speed mode allows the user to manipulate the inner rotor speed and the gimbal angle. It is designed for advanced users who independently derive the CMG steering and control laws.

FEATURES

  • High torque-to-power ratio compared with reaction wheels
  • Compact design allows for installation in a tuna can
  • Comprehensive software support and free technical support
  • Soft error and hard error fault detection
  • Magnetic leakage flux shielded with Ni-iron Alloy
  • Low jitter (micro-vibration) - ISO1940 G0.4 @ 8000 rpm
Specifications
Lead Time:
5 to 8 months
Angular Momentum Storage:
< 30 mNms for 2-axis
Angular Momentum Storage:
< 20 mNms for 1-axis (adjustable)
Torque:
< 3 mNm for 2-axis
Torque:
< 2 mNm for 1-axis (adjustable)
Inner rotor speed control accuracy:
< 5 rpm
Tilting angle control accuracy:
< 1 deg
Rotor imbalance:
ISO 1940 G0.4
Power consumption:
@ 5V bus < 4W
Power consumption:
@ 3.3V bus < 1W
Form Factor:
4x Tuna-can
Form Factor:
0.4U
Mass:
< 1000 g
Interface:
I²C
Interface:
UART
Interface:
RS485/422
Documents