Construction of Robotic Observatory - 4, Robotic Scope Cover

[Chanlunlun]

Dear ATMers,

No one can deny the importance of the telescope cover. Without it the primary mirror will soon be covered up by thick layer of dust. But the problem is – at 3 a.m. in morning nobody cares to open up the telescope cover for you. Your robotic telescope turns to be handicapped without a self–open cover !.

So we tried to make a robotic telescope cover and only to discover that it was much more complicated than what we originally thought of. We needed to construct a metal gear box for the stepper motor, write source codes ( in Visual Basic ) to program the parallel port of the computer, design circuit to interface between the parallel port and the stepper motor ( fortunately one piece of ULN2803 IC does all the job ) and we also needed to add lots of peripheral cards to our computer !!

After many hours of hard working we managed to put everything together. Though it looks poor in craftsmanship but the whole thing works. At least we are now having a telescope cover which could be operated via the internet.

Our next job is to fabricate a robotic flip mirror box, which, we belief, is an even more difficult job than to made a telescope cover.

Best regards
Chan Yuk Lun
21 Janurary 2009

[Chanlunlun]

more pictures...

[HK.Raymond.Tse]

Dear Chan Sir,

Good design through hours of hard work.

Can the scope cover flip all the way to rest on the tube ?
May not a problem if the scope is inside the dome.

It will be a problem for more exposed scope due to possible strong wind.

Would you mind to share your schematic design of the circuit ?

Raymond Tse

[syyuen168]

I notice the cover is made of laminated wood board. Would the durablity be increased by using a polyermic material ??

[Chanlunlun]

Dear Chan Sir,

Good design through hours of hard work.

Can the scope cover flip all the way to rest on the tube ?
May not a problem if the scope is inside the dome.

It will be a problem for more exposed scope due to possible strong wind.

Would you mind to share your schematic design of the circuit ?

Raymond Tse

Dear Raymond,

I am now drawing the circuit diagram and will post it here in the forum fery soon. Please stay tuned.

By the way it is a good idea to flip the telecope cover all the way round up to tube side. Since our telescope will be installed inside a dome and hence we choose not to do this refinement. But your idea is a very good one, especially in sliding roof type obsetvatory where wind force may be a destructive factor for star shooting.

Best regards
Chan Yuk Lun

[Chanlunlun]

I notice the cover is made of laminated wood board. Would the durablity be increased by using a polyermic material ??

Dear Mr. yuen,

Yes, plywood doesn't stand wearing very much. It look ugly too.

But, as usual, we are running out of money and so we choose ethe cheapest material. We plan to replace the cover by black arcylic sheet if extra funding is available.

Best regards
Chan Yuk Lun