Arne Bramigk, the main developer of the tip/tilt unit, today looks back on 10 years of successful development work, "the tip/tilt unit is in many ways of great importance for us. Today, we can so justifiably claim that our system is suitable for space. Who else can say that? This means both, ensuring its functioning at extremely high temperatures and in high vacuum. Even, for example, massive loads due to high accelerations during the start of the satellite must be coped with." But the basic requirement for the tip/tilt unit alone presented Bramigk and the team with great challenges: A displacement of ± 295 µrad, bandwidth of 300 Hz, and a resonant frequency (with load) of 1.3 kHz. "This could only be achieved by employing directly driven piezo tip/tilt mirrors; the mechanics is made of a special titanium alloy. In this project, we learned a lot about surface treatments and about FEM model calculations," Bramigk tells the inside story.
Dr. Joachim Woch, PHI project manager at the Max Planck Institute for Solar System Research, is pleased about the successful start of the mission: "The commissioning of PHI in space has been successfully completed. The first photos taken by PHI of the photosphere of the sun are of excellent quality. All technical subsystems, including the PI tip / tilt unit, work without any problems."