Large torque amplification and momentum storage capacity are the two basic properties that make Control Moment Gyroscopes (CMGs) superior when compared to the reaction and momentum wheels commonly used in spacecraft attitude control. These actuators have been used in a number of large spacecrafts such as ISS (International Space Station). For a specified torque level, single gimbal CMG based systems exhibit benefits in power requirements, agility, weight and size over their competitors such as reaction wheels.

Because of their inherent torque amplification property, CMGs are best for missions which require agility, such as stereoscopic imaging, formation flying, ISR (Intelligence, Surveillance, and Reconnaissance) missions, disaster monitoring, deep space scientific imaging missions and other high precision target tracking. Higher slew rates can be achieved by CMG systems with superior swap specifications.

Besides their many advantages, singularity problems (no torque capability along a particular direction) make the use of reaction wheels a real challenge. Hopefully in-house steering logics can avoid such undesired states for CMG operations.

Moment Control Gyroscope Flight Models and integrated driver & attitude control software have been developed and qualified (on ground) by Turkish Aerospace.



Turkish Aerospace also designed and manufactured Integrated Power and Attitude Control - Control Moment Gyroscope (IPAC-CMG) and 3-DoF Air Bearing Table for hardware in the loop attitude control performance testing.


Control Moment Gyroscope Operational Advantages:

Accuracy & Precision & High Slew Rate

Superior Solution for Precise Agility Missions

Stereoscopic Imaging, formation flying, ISR missions, Imaging missions

Saturation/Singularity Free Operation

CMG FM Angular Speed: 6000 RPM CMG FM Max Torque: 212 mNm
CMG FM Angular Momentum: 0.304 Nms CMG FM Shaft Max Speed: 6.67 RPM
Flywheel Mol: 4.83x10-4 Kgm2 Flywheel Balance Grade: < G1
Shaft Min. Speed Step: 0.62 °/S (Control Frequency = 10 Hz) Shaft Axial Mol: 1.18x10-3 Kgm2
CMG FM Mass: 8760 ±10 G Nominal Power Consumption: 21 W
Natural Frequency: 175 Hz Data Interface: EIA RS422
Operational Temperature Range: (-) 20°C ~ (+) 60°C Reliability:%91.2(For 1 Year)
Conforms to ECSS and Qualified on Ground (According to ECSS Testing 03A)
Cold Redundant Multi Node Data Bus