Because every gram weighs in

Turkish Aerospace is determined to significantly reduce the weight of structural components as part of the development of the TÜRKSAT 6A geostationary satellite. One of these structural elements is the so-called “Star Tracker“ bracket, which carries an optical measuring device that continuously records the satellite's position in relation to the constellation of stars and calculates its exact position in orbit.

The main components of the star tracker bracket were previously milled conventionally and then bolted together. In total, the bracket consisted of 360 individual parts and weighed 4kg.

Turkish Aerospace's goal was to use additive manufacturing to get a bracket that had to:

• have at least 30% less weight
• withstand the relevant acceleration forces during a rocket launch, and
• meet the relevant aerospace standards and guidelines.

The solution was in the design

The feasibility check performed at project start revealed that the original design of the star tracker mount could not reasonably be manufactured with AM. Topology optimization did not lead to a satisfactory result either, with regard to the goals. So we conceived a completely new design for the bracket as part of an ADM-E project.

To do this, the corresponding forces and frequencies were analyzed that the bracket was not allowed to exceed or fall below. On this basis, FIT experts used CAD software (Fusion and Inventor) to develop a design that featured a thin-walled, hollow shell geometry with internal bracing. This design was optimized by means of simulation and iteration (Optistract) so that it withstood the various load cases with high acceleration forces without falling below the defined natural frequencies.

The major advantage of this design was not only the high stability of the bracket combined with its low weight, but also its simplicity as it can be manufactured in one piece.

The special process requirements

The special challenge in the project was to develop a geometry that is both lightweight and extremely stable. The newly developed design and additive manufacturing of the bracket made this possible. Turkish Aerospace benefited from the following results:

• weight reduction of more than 50% to 1.96kg
• complexity reduction from 360 parts to one single part
• successful testing of the mount with acceleration forces of 20 G in all directions
• compliance with European standards and directives for the aerospace industry

Turkish Aerospace was won over by FIT's combination of industry understanding, design, and manufacturing expertise, as well as the extensive in-house quality assurance capabilities. You too can benefit from our range of services.