Arduino Ascom focuser Mark2

[wuthton]

This is something I want to sort out soon.  I have incremental focus control with push buttons which works well but I need to be out in the observatory warm room to control the focus - everything else (except opening and closing the roof) I can do from indoors.  Remote wifi focussing would be good - automatic focussing would be even better

I used it remotely last night with APT's FWHM and it worked like a charm.

[Mick J]

Good work Wuthton,  still working towards a very similar mounting, off the end of the dovetail.  Nice to know APT will work with it, always pleased to see a nice veil picture as well. 

[wuthton]

Good work Wuthton,  still working towards a very similar mounting, off the end of the dovetail.  Nice to know APT will work with it, always pleased to see a nice veil picture as well. 

Thanks for that! 

FWHM is so much more precise when using measured steps to focus.

[tekkydave]

Thanks for that! 

FWHM is so much more precise when using measured steps to focus.

I'll have to try that when I finally get to use my own focuser

[wuthton]

I'll have to try that when I finally get to use my own focuser

I feel like I've cheated with your girlfriend.

[Dave_D]

my initial test pic from 26th

and this one from yesterday

focuser works really well

looking forward to the next version of APT with autofocusing.

Edited July 30, 2014 by Dave_D

[wuthton]

looking forward to the next version of APT with autofocusing.

Me too!

[Yoddha]

I'm giving my best to release a beta version of the APT auto-focusing somewhere in the next week

[Yoddha]

The auto-focusing beta is here Anyone that wants to join?

Take a look here: http://stargazerslounge.com/topic/222399-beta-testers-needed-episode-2/?hl=%2Bauto%26%238208focusing

[wuthton]

The auto-focusing beta is here Anyone that wants to join?

Take a look here: http://stargazerslounge.com/topic/222399-beta-testers-needed-episode-2/?hl=%2Bauto%26%238208focusing

I couldn't test it last night as I had other commitments (unfortunately).

Thank you for the hard work, I'll certainly give it a go at the first available opportunity.

[Yoddha]

Thank you!

[Gina]

Thank you Ivo   I will be happy to test your Beta version when I'm in a position to do so.  A great addition to a superb app.

[Yoddha]

Many thanks Gina!

[tekkydave]

I have released Version 2.1.2 on the sourceforge site

https://sourceforge.net/projects/arduinoascomfocuser/

This minor change is to fix the issue with negative positions being allowed. I have been advised that it is not normal behaviour for an Ascom focuser to allow negative positions and it has caused issues with applications such as APT. The driver will now not allow movement below 0 and the Arduino sketch has been altered so it starts at position 1000 when powered up.

Hopefully that will be ok for everyone. I may add an extra property on the config form of the driver to allow a user-selectable start position in future but this should work for now.

I also need to implement the Halt command which would make it even more useful with APT. Next on the list I think.

Let me know if there are any other features you would like to see or leave some feedback on the SF site.

Thanks for using my project.

Edited August 9, 2014 by tekkydave

[tekkydave]

I have released V2.1.3 on sourceforge http://sourceforge.net/projects/arduinoascomfocuser/

I have implemented the following:

- The Ascom halt method. The method has been added to the driver and a H# command to the Arduino sketch.

- Initial position. This has been achieved by a new Arduino sketch command Innnn# to allow an initial position of nnnn to be set. I have added a text box to the Ascom chooser properties dialog to allow a user to set their preferred starting position.

I still haven't fixed the issue around driver registration but the workround is here http://stargazerslounge.com/topic/218975-arduino-ascom-focuser-mark2/?p=2365121

I have tested with APT, BYEOS and my FocusAAF2 test utility. Enjoy.

[orly_andico]

i did a different approach - because I don't know how to program in Windows, i re-implemented the Lacey / Moonlite protocol -

http://orlygoingthirty.blogspot.sg/2014/04/arduino-based-motor-focuser-controller.html

works fine for me...

[tekkydave]

i did a different approach - because I don't know how to program in Windows, i re-implemented the Lacey / Moonlite protocol -

http://orlygoingthirty.blogspot.sg/2014/04/arduino-based-motor-focuser-controller.html

works fine for me...

I did look at your site when I was considering my options. I wanted to learn Ascom driver development at the same time which is why I started from scratch. Its a good idea to reuse an existing protocol though.

[mindburner]

excellent project. I have just got a 200mm lens and I was going to try and build this focuser. Parts ordered to try the drive belt approach. I already have an arduino. I ordered an easy driver board so hopefully I will be able to use this with the arduino. 

Edited August 29, 2014 by mindburner

[tekkydave]

excellent project. I have just got a 200mm lens and I was going to try and build this focuser. Parts ordered to try the drive belt approach. I already have an arduino. I ordered an easy driver board so hopefully I will be able to use this with the arduino

Thanks for considering my project. I think the easydriver uses direction and step pin connections rather than the 4 separate lines my design uses. You will need to amend the clockwise() and anticlockwise() functions in my sketch to work correctly. It might be best to search out a sketch that uses the easydriver and 'borrow' the appropriate sections. If you get it working let me have a copy and I'll add it to the sourceforge project.

[russellhq]

Has anyone carried this out on an ED80? I'm scratching my head for mounting options and belt length. Don't want to reinvent the wheel if it's been done already

Also, not having the right tools I'm struggling to find info on the diameter of the focuser rod.

[wuthton]

Has anyone carried this out on an ED80? I'm scratching my head for mounting options and belt length. Don't want to reinvent the wheel if it's been done already

Also, not having the right tools I'm struggling to find info on the diameter of the focuser rod.

I used the dovetail bar. You can measure the required belt length with a piece of string.

[sulaco]

Hi folks,

I've come across this thread and I'm quite convinced about building my own Arduino focuser, can anyone tell me if the available drivers for this would work with Ekos and Indi protocol in order to use the autofocus function in Ekos?

[orly_andico]

The one that I wrote (link above) has been tested with INDI and works.

[russellhq]

Well that's the parts bought, let's see what happens when they turn up!

I decided to go for a direct drive rather than timing pulley. The shaft on the focuser is only 2.5mm, so it was difficult to find something with the correct bore. But I found these 2.5mm bore collars that are 8mm OD. And I found a 5mmx8mm flexible coupler, so hopefully they all fit together!

http://www.amazon.co.uk/gp/product/B00J995ZQM/

http://www.technobotsonline.com/zinc-collets-2.5mm-pk-4.html

[russellhq]

Would it be much extra work to include temperature monitoring? I know it's pretty straight forward, and cheap, to add a sensor to the arduino. I'm just not sure about the ASCOM driver side of things!