Active space-debris removal technology
The current glut of orbiting non-operational objects in space is generating an increasing concern about the safety of space for current and future space activities. Many space agencies, therefore, and in particular ESA, have started to launch space-debris mitigation projects. As part of this drive, future geostationary (GEO) and low-earth-orbit (LEO) satellites will have to carry out end-of-life removal maneuvers with a reliability rate of 90%. These will involve graveyard orbits for GEO and destructive atmospheric reentry for LEO.
Even if this 90% GEO and LEO satellite removal success rate is achieved in the future, ESA’s directive does not rule out future Active Debris Removal (ADR) missions to remove current space debris and also cater for any failures in the built-in removal systems of future missions. GMV is playing a key role in GNC design and development for ADR missions and net-based capture and removal techniques.
ESA has recently awarded GMV the Design for Removal (D4R) project, which sets out to increase the viability of future ADR missions, pinpointing all the concepts to be taken into account in the design, manufacture and operation of future satellites or launchers.
The concepts identified in this project will help ADR missions in a series of key aspects such as identification of aids to support tracking and estimation of debris position and attitude both from earth and in orbit as essential baseline knowledge for any removal operations and for defining the characteristics of the ADR mission. Another key aspect to be dealt with will be attitude stabilization, since tumbling debris can impose strong constraints on the capture, stabilization and disposal of the debris. Lastly, an identification will be made of aids to facilitate debris capture and subsequent removal.
Active Debris Removal is a complex task that has not yet been fully demonstrated. The D4R initiative thus represents a significant stride forward in the endeavor to protect future space activities.