On-Orbit Service

On this planet, we need services in every aspect of our life. This could be for example maintenance service for our cars, or regular repairment service for our houses. And, of course, the satellites surrounding our planet also need service: they need to be re-fueled when the fuel is gone and the non-functioning components need to be replaced with new ones. The technology to provide these services is called On-Orbit Service (OOS).

The most famous example of OOS is the correction of the flawed main mirror of the Hubble Space Telescope by astronauts onboard the space shuttle, shortly after the telescope was deployed in 1990. Another interesting application of the OOS technology is the Phoenix concept, which aims to re-use the functional components of non-functioning satellites to assemble a new satellite in orbit by making use of space robotics.

Phoenix concept (copyright: DARPA)

At Space Systems Engineering, we are working on a new application of the OOS technology, called Active Debris Removal (ADR). Our objective is to explore the possibilities for safely removing part of the roughly 200 million items of debris surrounding the Earth, in order to protect our space assets and, more importantly, the space environment for our future. One of the most promising debris capturing approaches of ADR is a tethered-net, which has the capability to capture a tumbling piece of debris by deploying a flexible net (similar to a fishing net). Hereafter, the debris is dragged into the atmosphere to burn up, using a tether that is linked with the net.

Capturing debris using tethered-net (copyright: ESA)

One of our projects on ADR is the dynamic characterization of the tethered-net. To achieve this, we developed various mathematical models of tether deployment and verified them through the results of parabolic flight. Now we are looking forward to an in-orbit verification of our models!

The deployment dynamics models