A compact telescope shelter

By Olivier Garde & François Cochard

The open shelter (photo : François Cochard)

Having a fixed installation is a dream for many astronomers, amateurs as well as professionals. This is particularly the case in spectroscopy, because the installation of the equipment may take a few hours. Then, there are two main families of solutions: either a dome or a shelter. Each solution has advantages and disadvantages…

Within Shelyak, we needed a shelter that would allow, in the long term, to make robotic observations with a small instrument. Not finding in the market a solution that meets all our requirements… we have designed “the ideal shelter” for our need. And as it seems to us that many observers might be interested, we plan to commercialize this shelter in the coming months.

It’s a compact shelter to house a small telescope (typically a SCT of 200 to 250mm in diameter). The useful volume for the telescope is a cylinder of 1,15m in diameter.

It allows to leave the instrument on its mount (or on a pillar) outside and protects the whole of the rain, the snow, the wind and the sunlight during the day.

This all-metal shelter (stainless steel for the base, painted aluminum for the roof) can be installed discreetly in a garden or on a terrace.

It is fully motorized, and remotely controllable (in the current state by Python commands). Powered by 12V (min 10A), it has a backup battery, which ensures automatic closure in case of power failure.

The shelter allows a complete clearance of the horizon, up to about 10 ° of height. In the open position, we completely forget the shelter (while with a dome, we must enslave its position to the telescope). In case of wind, it is possible to make a partial opening of the roof (each half-roof can be controlled to the millimeter).

The opening and closing can be done whatever the position of the telescope. No need to put the telescope in “parking” position before closing.

No moving parts inside the shelter: no risk of pulling cables during the movements of the telescope.

The whole electronics (protections, power supplies, Raspberry Pi, etc.) is installed in an electrical box near the shelter.

Technical characteristics

Internal dimensions : 1150 x 1150 mm
Height of the fixed part : 1000mm
Total height : 1600mm.
Weight : about 100kg

The roof and 4 side panels are easily disassembled for full access to the interior.
Access doors at the bottom of the shelter.
30mm Bosch profile structure (standard).
Easy on-site assembly (no bulky parts for transport) .
The movement of the roof is ensured by four large threaded rods (M16, stainless steel). All moving parts are mounted on ball bearings (40 ball bearings in total).
Threaded rods are driven by four stepper motors. Each motor is controlled by its Arduino-based electronic board. The control of the entire shelter is made by a Raspberry Pi, with software in python. All is open source: all the software (Arduino & Python) are available for a deep customization, if needed.
Lighting integrated at the four corners of the shelter with remote controllable white LEDs.
Power supply 12V, 10A (not included).
Floor fixing with 8 M8 screws (ideally in a concrete slab).