VLT sensor arm

Modern telescopes are wonders of technology and precision engineering, with their accurately crafted mirrors and lenses, along with a slew of high quality electronics. 3D printing could drastically alter how telescopes are built and how powerful we can make them, letting us see further into the depths of the universe.

Apart from the Hubble telescope and the upcoming James Webb telescope, telescopes don’t get much better than the ESO’s Very Large Telescope (VLT) array in Chile. Due to the nature of astronomical optics (aka star gazing), spare and upgraded parts are often expensive and hard to source for these telescopes. Thanks to 3D printing, the ESO was able to produce two essential components for a better price and much more quickly.

The first component component printed was a new ensor arm that will be installed into the telescope in order to work with the ESO’s MUSE instrument – a panoramic integral-field spectrograph for studying the universes galaxies. ESO’s MUSE instrument will be supplemented with an optics module in 2015, named GALACSI. The 3D printed metal sensor arm holds three mirrors that guide and direct light into the VLT’s sensors.

Germany’s Voxeljet 3D printing company printed the part for VLT. First the part was cast in a thermoplastic, polymethlmethacrylate and then wax was used to create a negative of this shape by pouring it into the plastic print. A heat-proof ceramic is used to coat the wax, resulting in a die that creates the final metal cast. The new aluminum sensor arm replaces a highly toxic beryllium arm, which is not safe to modify after instillation.

ESO enlisted the help of German metal casting company,ACTech GmbH to produce the second component, a spacer for the VLT’s test camera. The spacer will be made via investment casting from ductile cast iron, with the mold being crafted from selective laser sintering.

below is a cool timelapse video from the VLT array.