Arcsec

The demand for high resolution earth observation images, high data rate communication, and novel science missions has increased the focus on attitude determination and control systems performance. This is specifically true for the SmallSat market as SmallSats and CubeSats are increasingly being utilized for missions that require pointing performance in the range of arc seconds.

Enter arcsec—a spinoff company of the KU Leuven University in Belgium. Arcsec offers high accuracy attitude determination and control systems (ADCS) for CubeSats and SmallSats.

“Our ability to deliver superior attitude determination and control accuracy in a compact package has made us the go-to supplier of the highest accuracy ADCS systems for the most demanding missions,” states Tjorven Delabie, CEO, arcsec.

Arcsec’s product portfolio includes fully autonomous ADCS, star trackers, and reaction wheels. The star trackers determine a spacecraft’s orientation in space based on the location of the stars as displayed in the image, along with the positions of stars in existing databases. The Sagitta is arcsec’s most accurate star tracker and offers arcsecond range pointing knowledge to the satellite. It comes with custom algorithms, designed to work effectively with small optics.

Arcsec’s second star tracker—Twinkle— is as small as a Matchbox car and delivers pointing knowledge in the range of arcseconds. The low mass and power consumption of both star trackers allow to incorporate multiple sensors into a spacecraft, increasing accuracy and availability.

Arcsec’s reaction wheels utilize high accuracy speed sensors and an internal speed control loop to deliver precise attitude control.

“Our custom motor design leads to high torque and momentum capacity within a small package. This allows CubeSats and SmallSats to perform very agile maneuvers, making the most out of their mission”, says Delabie.
Arcsec understands that SmallSat developers often lack the resources to set up a strong in-house ADCS team that can cope with all the intricacies of spacecraft pointing. In response, the company offers user-friendly products and tools that can be easily deployed and tested. Arcsec provides a star simulator used to test the star trackers. It performs pointing analysis and other simulations to analyse how well the ADCS performs for different missions and pointing modes. Arcsec also provides electrical ground support equipment and graphical user interface software with all components that it sells.

Arcsec’s products have gained huge traction over the past few months due to their high performance and accuracy. Several CubeSats in orbit are relying on Arcsec’s systems for precise attitude determination and control. For some missions, the ADCS is even a “mission saviour.” On one mission e.g., it was found that one of the payload sensors was not available during the sunlit period as it did not deliver reliable measurements at high temperatures. Fortunately, the flexible pointing mode management of arcsec’s ADCS allowed the client to shift to a new pointing mode, which keeps the sensor in the shadow side of the spacecraft. This has enabled the payload sensor to deliver reliable measurements throughout.

In the coming years, arcsec will further expand its product portfolio, moving in the direction of larger platforms and ever higher accuracy.