Reaction Wheel for pico & nano satellites
The compact reaction wheel is especially designed for attitude control used in pico or nano satellites. Due to its cube shape with integrated electronic control it can be used in several configurations. The reaction wheel is provided with vacuum-rated bearings and components resisting radiation terms up to 200 Gy. Profiting from the experience of WITTENSTEIN cyber motor in the field of precise small permanentmagnet motors and ZFT in the field of reliable space electronics and software engineering.
Project NetSat

A complete observation of an object without blind spots requires the combination of images from different perspectives. We also want to avoid hidden points when observing the Earth, in order to set new standards in the three-dimensional observation of our planet and to be better positioned for future communication networks.The Centre for Telematics in Würzburg has developed four CubeSat mini-satellites (mass <4kg) for this purpose and launched them on 28 September 2020 from the Plessezk Cosmodrome into an orbit 600km above the Earth using a Soyuz rocket. On board are six WITTENSTEIN cyber motor reaction wheels per satellite. A radio link enables data exchange between the smallest satellites, which allows various manoeuvres to be carried out. The cyber® reaction wheel 2 takes over the position control in x-, y- and z-direction.
Excellent solution for ambitious missions
Compactness
- 20 x 20 x 20 mm (L x W x H)
- < 30g
Efficiency
- 5 V supply voltage
- < 300mW power consumption at nominal speed
Precision
- Individually balanced to reduce vibration
- Self-calibrating control algorithm
- Multiple optimization patterns
Robustness
- Radiation up to 200 Gy
- -40°C to +85°C operating temperature
High performance density
- Momentum storage: 2,0 mNms
- Max. rotation speed: 20.000 rpm
- Nominal torque: 0,1 mNm
Connectivity
- UART
- I2C
- SPI
Technical construction
Extremely compact in a square space of 20 x 20 x 20 mm, the Reaction Wheel is especially designed for rough space conditions. The square construction makes space-saving integration possible and, with its low torque / weight ratio it provides maximum flexibility in the application. The efficiency, robustness and compactness characterize the Reaction Wheel.
Momentum storage 2,0 mNms
20 x 20 x 20 mm (L x W x H)
Designed for harsh space environment
0,1mNm nominal torque
Flexible Interface
Situation aware control system
Hot restart failure recovery
Fire-and-forget control or programmed profile control
Technical data
Performance | |||
Momentum storage (@20000 rpm) | 2,0 mNms | ||
Nominal rotation speed | 20000 rpm | ||
Nominal torque | 0,1 mNm | ||
Mechanical | |||
Mass | < 30 g | ||
Dimension | 20 x 20 x 20 mm | ||
Electrical | |||
Supply voltage | 5 V | ||
Operating voltage | 3,3 - 8,4 V | ||
Power consumtion at nominal speed | < 300 mW | ||
Power consumtion at peak | < 1000 mW | ||
Environmental |
| ||
Operating temperature | -40°C to +85°C | ||
Survival temperature | -60°C to +100°C | ||
Operating time | 25000 h |
System
For a 360 ° alignment of the satellite, the Reaction Wheels can be positioned in various arrangements.
The most common variants are shown below:

Tetrahedron on board

Wheels on grid
Starter kit

For commissioning, we offer the reaction wheel starter kit, whereby the reaction wheel can be put into operation within a few moments using a PC and the MotionGUI 2 graphical user interface. This also allows diagnostics, optimisation and parameterisation to be carried out.
Downloads
Contact us
Is there anything you'd like to know about the Reaction Wheel? Do you require personal advice?
If so, please contact us directly. We look forward to hearing from you!