The ATV-5 is the last European transport vehicle for the time being to reach the ISS. Alongside food for the crew and scientific experiments, two sensor types from Jena are also on board. The next generation of the Rendezvous- and Docking Sensors (RVS) has been deployed for the first time in the form of the newly developed RVS 3000, a 3D LIDAR. The development and manufacturing of this sensor prototype for ATV-5 was conducted for Airbus Defence & Space on behalf of the ESA.
The way forward into the future has been initiated with the RVS 3000, which has had its maiden flight on ATV-5. The new high-precision sensor is smaller and lighter and is characterised by its use at greater distances and increased flexibility due to the changeable field of view of the RVS3000.
“The flight on ATV-5 gives us the opportunity to test this new technology as a “passenger” in a real space environment and to record data. These data will form the basis for future sensor developments, to gather and catch space debris for example, or to land safely on other celestial bodies”, explained Dr Florian Kolb, head of the LIDAR department at Jena-Optronik. He went on to explain: “Everybody pulled together to make the project successful in spite of the tight time frame. In particular, the joint effort of the German, French and Italian teams was a prime example of European cooperation. I would like to express my gratitude for the great commitment and flexibility of all parties involved.”
To enable an unimpeded approach to any object in space, high-performance sensors are required. 19 of these laser-based RVS sensor systems have already been successful in outer space.
The latest generation of sensor, the RVS3000, will have its maiden flight as an experiment with the project name “LIRIS-2” (Laser InfraRed Sensor) on the next European transport vehicle ATV-5. The application of the sensor on ATV-5 is an important milestone as a pre-qualification for use on future missions, such as the German DEOS (German Orbital Servicing) mission by DLR German Space Agency, but also shows the versatility of the sensor for future international use on commercial spacecraft.
RVS3000 works in a range of 1m – 3000m against retro reflectors, and up to >1000m against diffusely reflecting surfaces. The scanner field-of-view may be varied up to 40deg x 40deg, with an image rate of 1Hz – 4Hz in general.
The project excelled in its close cooperation with the Fraunhofer Institute for Applied Optics and Precision Engineering (IOF) in Jena, which was responsible for the fiberoptical and mechanical components of the laser and played a key part in the development of the space-qualified fiber laser. The development of the space-qualified electronics of the laser was done by Jena-Optronik. For this purpose, the laser generates a ns-pulse, which is sent to a defined position in space. If the pulse comes into contact with an object, a part of its energy will be scattered back to the sensor. The time of flight between reference and back-scattered pulse can now be translated into a distance. By repeating this procedure for different spatial directions and at different pulse repetition a 3D image can be generated in less than a second.