The automatic deployment of these metallic blue 'wings' and the activation of the on-board navigation systems will transform the 20-tonne Automated Transfer Vehicle (ATV) into a fully automatic spaceship navigating towards the International Space Station (ISS).
"The test went well despite the fragility of the solar arrays. It proves that the ATV solar power, designed for up to six months in orbit, is working fine", said Detlef Otto, who is in charge of the ATV power system for ESA and who supervised the test.
The bus-sized ATV spacecraft had to be rotated into a horizontal position for the integration of the solar panels. The panels were fully deployed and then folded again and latched, ready to fly. Each panel was minutely inspected before final integration.
Since the solar arrays have been engineered to work in weightlessness, their 9.15 m-long structure is so light that they cannot be unfolded on Earth without being supported by several cables. “Otherwise, in Earth's gravity, the solar panels could not hold their own weight of 7kg without bending irreversibly”, said Detlef Otto. The system is so sensitive that during the arrays' deployment tests even the barely noticeable air conditioning flow had to be turned off in the huge integration hall.
But the five-year effort to develop the ATV 'wings' and their rotation mechanisms, that enable the outstretched solar panels to constantly track the Sun as the ATV circles the Earth, have been a challenge until recently. During several years of testing, the state of the art solar panels have been deployed and checked about 50 times by the engineers at Dutch Space, who built them.
Some tricky issues related to the solar panel rotation mechanisms, built by Thales Alenia Space in Cannes, France, have put some pressure on the timeline. Constant tracking with these mechanisms permits the most efficient generation of electrical power for the ATV in orbit and during its six-month long ISS docking phase.
The four 4-kg rotation mechanisms have been checked and removed from the ATV several times to solve some minor problems of resistance and lately, some contamination issues due to metal particles found in one of the mechanisms.
Once deployed, the four solar arrays provide electrical power to ATV and to its rechargeable batteries so that the eclipse periods in orbit can be bridged. Silicon-based solar cells, developed and produced in Germany by RWE Space Solar Power, cover the four panels per array with a total surface of 33.6m² (4 x 8.4m²), and are able to produce an average of 4800 Watts.
Mounted on the ATV service module, the four sun-tracking arrays are totally independent and can get the best orientation to the Sun thanks to the rotating mechanisms. The ATV solar power sources are built to tolerate the loss of one of the four independent arrays and their respective power chains.
“Now we feel confident, although the next challenge will be the 6-month attached phase with the Station because he ATV wings will have to withstand millions of vibrations and oscillations due to the ISS crew activity and the Station jets”, said Detlef Otto.
Markus Bauer | alfa
Hubble sees Neptune's mysterious shrinking storm
16.02.2018 | NASA/Goddard Space Flight Center
Supermassive black hole model predicts characteristic light signals at cusp of collision
15.02.2018 | Rochester Institute of Technology
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
Let’s say the armrest is broken in your vintage car. As things stand, you would need a lot of luck and persistence to find the right spare part. But in the world of Industrie 4.0 and production with batch sizes of one, you can simply scan the armrest and print it out. This is made possible by the first ever 3D scanner capable of working autonomously and in real time. The autonomous scanning system will be on display at the Hannover Messe Preview on February 6 and at the Hannover Messe proper from April 23 to 27, 2018 (Hall 6, Booth A30).
Part of the charm of vintage cars is that they stopped making them long ago, so it is special when you do see one out on the roads. If something breaks or...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
16.02.2018 | Information Technology
16.02.2018 | Health and Medicine
16.02.2018 | Physics and Astronomy