In space, the rules are different: extreme temperatures, a vacuum, cosmic radiation, and decades of operation require sensors that are absolutely reliable and durable. This is exactly where potentiometric angle sensors based on Leitplastik come into play. In demanding space applications such as the alignment of solar arrays and antennas, they have proven themselves to be a robust and precise solution—making an unobtrusive yet crucial contribution to the operation of satellites and space probes.
Challenge: Precise positioning under extreme conditions
Whether it’s Earth observation satellites like the Sentinel series or interplanetary missions like BepiColombo—all rely on large amounts of solar energy. To do this, the solar arrays must be continuously pointed toward the sun. This task is handled by special Solar Array Drive Mechanisms (SADM), as well as similar drive systems for communication antennas.
Reliable and long-term stable position detection is essential for their precise control. The sensor system must:
- operate in a high vacuum
- withstand extreme temperature fluctuations
- withstand decades of storage and use
- be resistant to cosmic radiation
- provide precise absolute measurements
- take up minimal space
The choice of technology is therefore critical to the operational safety of the entire mission.
The solution: Potentiometric angle sensors from Novotechnik
Earlier space projects used optical encoders, but their sensitive components required extensive protective measures in space. As a result, the aerospace supplier Kongsberg Defence & Aerospace sought a more robust technology—and found it in Novotechnik’s conductive plastic potentiometers.
Why potentiometers in space?
- No semiconductors, no radiation issues
- Absolute encoders with analog signals ready for immediate use
- Low wear and long-term stability, even after millions of cycles
- Not affected by temperature or environmental conditions
- Cost-effective compared to other high-precision technologies
- Fully customizable
For space propulsion systems, Novotechnik developed a redundant rotary potentiometer consisting of two independent sensor circuits, thereby ensuring maximum reliability.
Custom-designed structures for space missions
The special potentiometer is based on a proven standard design but has been fully adapted to meet the requirements of the SADM and antenna mechanisms.
Design features:
- Two stators and one rotor made of durable FR4 composite material
- Redundant configuration for reliable duplication of the measurement signal
- Large inner diameter, ideal for routing cables or RF conductors
- Flat, lightweight design, ideal for aerospace-grade mechanisms
- Simple electrical connection via three wires
- Pure analog signal, ready for use immediately without additional electronics
The sensor system provides precise angular positions—regardless of temperature, vacuum, or radiation.
Successful tests in a high vacuum
Before potentiometric sensors are certified for real-world missions, they must undergo extensive testing. The space-grade potentiometer developed passed:
- 13 Millionen Zyklen im Hochvakuum < 1 mbar
- Range of motion: 205° on average
- No measurable deviations
- Virtually no wear on the resistance tracks or grinders
The sensor thus met all requirements—and in some cases exceeded them by a wide margin. Even long storage periods prior to launch (up to 20 years) are not a problem.
Use in current and future missions
Novotechnik’s conductive plastic angle sensors are now an integral part of many satellite programs. Typical operational lifespan in space: 10–12 years —reliable and maintenance-free. They will continue to be on board future missions as a precise, robust, and radiation-resistant solution.
