Hi,

I'm in the process to build an observatory with a roll-off roof that I would to be automated and controlled by Kstars/Indi. Nothing is built yet so everything is open.

I'm looking for information here and there to find the best solution for me and my skills.

Lunatico has their Dragonfly controller which pretty much does the job but it seems overkill just to open/close the roof, and it's also pretty expensive. Any feedback?

What are the other solutions you guys are using? Do you have any resources/links which could help me deciding?

Thank you!

steve

If you'd consider DIY solutions then I'd recommend the OCS system: onstep.groups.io/g/onstep-ocs
Obviously it's not for everyone depending on your skill set and requirements but very capable, customisable, and cheaper.

Thanks Ed.

Any other recommendation?

I use this with a sliding gate opener.
github.com/indilib/indi-3rdparty/blob/ma...rolloffino/README.md

I built this one for my ROR and its been working well since about 2016.
github.com/dokeeffe/indi-aldiroof

My only recommendation is to try to use one of the existing INDI drivers rather than writing your own and having to maintain that code as INDI updates.
I'm using the INDI driver called dome-scripting-gateway. It allows me to call a script to open the roof. Then you can do whatever custom stuff you want in the script. All my scripts are in this directory github.com/dokeeffe/indi-aldiroof/tree/m...pting-gateway-driver

I do not know why, but I was always afraid to integrate my roof-gate opener with Ekos into the same system. Probably afraid of failure.
That's why I left it dead simple with just the hand controller and the eWelink app which powers on/off the Sonoff controller.

For me the main advantage of integrating with Ekos is for weather. I have a rain monitor integrated too and if it rains, Ekos parks the scope and closes the roof.
I live in Ireland where rain can come at anytime

Dear all,

Thanks a lot for all your feedback. I'll dig into them and see what suits me best, the goal being to have a complete Ekos/Indi setup.

Best,
steve

I had a look at github.com/indilib/indi-3rdparty/blob/ma...rolloffino/README.md and it seems pretty good.

But since I'm a complete novice in this fields, I was wandering if there was any specific type of motors to be used or if any motor would do. Any pointers?

Also, I had a look at arduino, which I already heard about but never used, and there are plenty of different models. Which one would be a good start, knowing that reliability is the main concern? I mean the roof MUST close when it has to (rain, snow etc), so the setup must be industrial solid.

Thanks

100% agree. It must be industrial solid. The roof mechanics, motors, relays and script/driver needs to be as reliable as you can make it.
I built my roof opening system very cheaply using a workshop hoist motor from Aldi combined with a rack and pinion from an automatic gate system, some relays and a raspberry-pi. It took me some time and a lot of testing on the mechanical side to get it reliable. If I were to go back in time and rebuild this. I think I would choose one of those automatic gate opening systems. I mean the full thing, the motor, mechanical parts and the electronics of the controllers. I think other people have used these. Maybe someone can comment here.

Perhaps the easiest DYI path is to select a commercial garage or sliding gate opener. One that has uses one or two buttons to activate open or close. You first install and get that working reliably to operate the roof. Then you interface INDI with the controller rather than a particular motor. All the interface has to do is close a relay that parallels the controller's normal switch.

You could then try the INDI scripting interface and see how you get along.

A bit expensive but one of the more impressive (industrial strength) DYI installs I have seen is entry #20 at:
www.cloudynights.com/topic/816370-aleko-...-reliable-openclose/
He uses an ASCOM driver and scripts that he offers to share and from which I imagine an INDI solution could be formed.

Some comments from a view of using the rolloffino driver.
It is a DIY solution, both the hardware and any Arduino software changes is up to the user. So should be comfortable making at least minor Arduino code changes and loading them onto the board. One thing to understand is the INDI driver just sends open/close requests and asks are you done yet. It does not know what is going on at the other end. Using a roof controller takes care of stopping the roof when it gets to the end of its run.

I use a Arduino Uno R2 with a relay shield attached on top. They have a new higher performance 3.3V based Uno R3, and it can work with the 5 volt shields. If using a roof controller and you choose a shield that matches the default settings in the Arduino then might not need to make changes just load the example code. One thing nice with the Arduino is that it has been running from year to year without any intervention. Power outages seem to always cause manual intervention except for the Arduino it just reboots restarts and chugs along.

I am not happy with my own install because it does not have soft start/stop.
With a heavy roof it is a bit too rough. Depending on the size of the observatory Aleko offer 3 openers with soft start/stop. The stronger ones were sold out last time I looked.

Mechanics aside, which of course need to be as reliable as possible, in my opinion one of the big differences between most DIY systems and something like the Dragonfly or OCS controllers is the level of safety they provide for your equipment. These systems provide the means to connect up weather monitoring kit and independently act on it's data regardless of a software connection. They run minimal internal software on a micro-controller. This is much more simple and robust than any software system running on an OS. There are just too many things that can go wrong to rely on only a typical software controller - connection failures, software crashes, OS crashes, updates/reboots, hardware failure. This is why industrial machinery still uses PLC's and micro-controllers for anything that must be provably safe despite the relative lack of flexibility compared to a software solution.

These systems provide for connection to and control from INDI/ASCOM but will but (when so configured) will take independent safety actions themselves. With a UPS in the solution anything short of mechanical failure or a lightning strike is pretty well covered.

Of course nothing is perfectly robust...