Primary mirror cell with active optics for lightweight telescopes of medium size

Short Description

Starting point / motivation

Currently, midsized telescopes with a diameter between 0,6 m and 2,0 m are gaining increased importance in several established as well as in newly emerging applications.

Optical communication with satellites in the orbit, which enables more than ten times higher data rates than available radio frequency communication systems, and the identification and tracking of space debris, in order to reduce the risk for functional satellites, are two examples for applications requiring midsized robust telescope systems with sufficient light-gathering power as a fundamental prerequisite.

To guarantee appropriate reliability of these systems, a large number of optical ground stations is required. This makes a low system mass of telescopes, allowing for easy transportation and installation, as well as low production costs a desirable property.

For reducing the weight of about 1500 kg and costs for production, transportation and installation of current, comparably heavy, telescopes in the 1-m class, thin lightweight mirrors can be employed to reduce the mass of the primary mirror, which is the driving factor for overall system cost and weight.

Contents and goals

To avoid a degradation of the imaging quality caused by deformations of the thin mirror due to gravity, this project aims to develop methods for the development and integration of an active optic system into the primary mirror cell of telescopes by the industrial partner ASA Astrosysteme GmbH in the 1-m class.


The active optics enables to compensate for orientation dependent gravitational sag thermally induced deformations by an active correction of the mirror by using an active axial and lateral suspension system. Following an integrated mechatronic system design approach an extremely lightweight design, a high imaging quality of the system as well as an exceptional cost efficient solution are to be obtained.

In this course, a modular concept for the system design will be developed, including methods for the optimal number and placement of actuators over the mirror surface and modular highly integrated actuator-sensor-systems. An optimal system integration systematically will consider the interplay between the system components, the system requirements and the real time control system and will enable the design of lightweight telescopes with highest optical quality.

With a mass in the range of 500kg the resulting telescope system will be easy to relocate and install and will provide large light-gathering power. Additionally, the developed system will ensure an increased robustness with respect to environmental influences, such as temperature, which decreases the cost of the surrounding infrastructure.

Expected results

The results of this research project will enable ASA to extend their product portfolio to these new and currently emerging markets and to strengthen the position on the international market as a leading player in the midsize telescope sector. This will have a positive effect for the company as well as for the Austrian high-tech sector, employment rates and the overall economy.

Project Partners


Vienna University of Technology

Project partner

ASA Astrosysteme GmbH

Contact Address

Vienna University of Technology
Karlsplatz 13
A-1040 Vienna
Tel.: +43 (1) 58801 0
Fax: +43 (1) 5880141275