CMG-20m Control Moment Gyroscope

CMG-20m has two variable-speed, single-gimbal Control Moment Gyroscope (CMG) which is suitable for 6U CubeSats. Unlike traditional CMGs, each driven by two or three motors, this CMG is each driven by only one spherical motor, making it capable of minimizing into a CubeSat form factor.

Serving as an attitude actuator component, the CMG-20m has to be commanded by the user's onboard computer (OBC) or ADCS computer. Torque and speed modes are available for the OBC or ADCS computer to switch between.

The user's controller design can be simplified by adopting the torque mode. However, the output torque is only accurate when the satellite has 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 will derive the CMG steering and control laws by themselves.

The system achieved flight heritage in 2022.

Features

  • Offering improved torque at lower power consumption versus reaction wheels
  • Cost effective solution with high performance
  • Compatible with a wide range of satellite configurations
  • Comprehensive software support and free technical support
Specifications
Lead Time:
4 to 7 mo
Angular Momentum Storage:
< 20 mNms for 1-axis
Angular Momentum Storage:
< 10 mNms for 2-axis (adjustable)
Torque:
< 2 mNm for 1-axs
Torque:
< 1 mNm for 2-axs (adjustable)
Inner rotor speed control accuracy:
< 5 rpm
Tilting angle control accuracy:
< 1 deg
Rotor imbalance:
ISO 1940 G0.4
Power consumption:
@ 5V bus < 1W
Power consumption:
@ 3.3V bus < 1W
Form Factor:
2x Tuna Can
Form Factor:
0.2U
Mass:
<500g
Interface:
I2C
Interface:
UART
Interface:
RS485/422
Optional:
GNSS system and 3-axis magnetorquers
Documents