USB Focusers

[Shelster1973]

Quick question ..... can you use BYN to drive a USB connected stepper motor focuser?

 

Reason for asking is am going to be adding one to my set-up and have an ASCOM compliant driver for the stepper motor affair, so was wondering if it is possible that I can have BYN control this or would I need another piece of software...

 

Cheers

[fjeske67]

(Moved from wrong thread)

 

Got the hardware side of the motorized focuser together as seen here http://farm8.staticflickr.com/7563/16159177139_466d49ebe9_b.jpg

 

Still haven't run it all together so I expect some tweaking of positions, etc.

 

Once I get it finalized I'll post a disassembled version and list out all the parts.

 

One piece of equipment I needed was a drill press to make this, which I always wanted anyways.

 

Felix

[fjeske67]

(From other thread)

 

How much does it weigh?  It looks heavy?

 

I don't think too much but I popped out the kitchen scale and measured it.  I think the perspective of the picture makes it look more bulky than it is.

 

The original focuser knob assembly is 9.6 oz (almost solid Al).  I've added 19.5, of which the motor is 6.5 oz.  Too heavy?

[fjeske67]

So I got everything running today and had to replace the small pulley on the focuser to something much larger to reduce the load on the motor.  So I now have 16 teeth on the motor vs 36 on the focuser giving me some extra gearing.  I also had to adjust the motor speed down to 36 rpm max.  This was mostly due to the weight of the camera on the focuser with the motor potentially needing to pull the load straight up.

[fjeske67]

The software side of the Arduino board with stepper driver is now working under BYE via the ASCOM Focuser module I found here ( I had to modify the board programming a bit since it seemed to be tailored for another model so I had to customize it for my Seeed Motor Shield (http://www.seeedstudio.com/wiki/Motor_Shield_V2.0).

 

The next task is to actually mount the stepper/board combo somehow on the focuser itself.  The rubber wheel I bought doesn't look like it'll work since it slips too much on the gear I mounted on the stepper.  I'll have to move on to Plan B which looks to be a toothed belt between the stepper and focuser.  Seems that a lot of robotic projects do this so I just have to find the right combination of parts and a custom mounting bracket.

 

Only concern at the moment is the speed of the stepper.  It'll only do 60 RPM max which looks to be slow, especially on the fine control knob which is already 10:1.  I guess I can play with the pulley sizes for the belt to increase this if necessary.

 

Felix

[fjeske67]

Can't edit the above post, fixed missing link below.

 

The software side of the Arduino board with stepper driver is now working under BYE via the ASCOM Focuser module I found here ( I had to modify the board programming a bit since it seemed to be tailored for another model so I had to customize it for my Seeed Motor Shield (http://www.seeedstudio.com/wiki/Motor_Shield_V2.0).

 

The next task is to actually mount the stepper/board combo somehow on the focuser itself.  The rubber wheel I bought doesn't look like it'll work since it slips too much on the gear I mounted on the stepper.  I'll have to move on to Plan B which looks to be a toothed belt between the stepper and focuser.  Seems that a lot of robotic projects do this so I just have to find the right combination of parts and a custom mounting bracket.

 

Only concern at the moment is the speed of the stepper.  It'll only do 60 RPM max which looks to be slow, especially on the fine control knob which is already 10:1.  I guess I can play with the pulley sizes for the belt to increase this if necessary.

 

Felix

[fjeske67]

OK, it's not me, editor is eating the ASCOM Focuser link:

 

... the ASCOM Focuser module I found here (http://sourceforge.net/projects/arduinoascomfocuser/files/Mark2/Software/V2.3.0/).

[admin]

OK, it's not me, editor is eating the ASCOM Focuser link:

 

... the ASCOM Focuser module I found here (http://sourceforge.net/projects/arduinoascomfocuser/files/Mark2/Software/V2.3.0/).

 

I think it is because you have the parenthesis part of the href link in your post above.

 

Regards,

[astroman133]

BYN Beta and BYE Premium versions can control correctly installed ASCOM-compliant focusers (as well as mounts and filter wheels.  Your question asked specifically about USB-connected focusers.  That depends on the driver for the device.  If the driver supports connection by USB, then the answer is Yes!

 

You need to have the ASCOM Platform installed (preferably the latest release), along with the driver and any additional software that is required by the driver.

 

You can test BYN with the ASCOM Simulator Focuser Driver.  BYN and ASCOM won't know the difference.  And you can watch the changes that BYN is making by examining the focuser position value in the simulator's popup window.

[admin]

If your focuser has an ASCOM compliant driver then it should connect.

 

Guylain

[Shelster1973]

Cheers all.

 

Will give it a try when I sort out my new imaging laptop.

[fjeske67]

Hello all, new to BYE and this forum.

 

Just tried out my Stellarvue SV80 last week in the backyard and quickly discovered that I probably need a motorized focuser as mentioned above (I drive the mount/DSLR via a 65 ft USB cable so I can stay warm inside).

 

So what is the actual recommended hardware for this?  Most of my Google searches found equipment in the near $500 range for this.  Are there less expensive/possibly DIY solutions for remote motorized focusing?

 

Thanks,

 

Felix

[Shelster1973]

Hi

 

Not done it myself but you can use a Stepperbee kit with some rubber friction wheels which will work.

 

I have the drivers and info on my computer (posting from phone while away atm) if you are intereste? Will have to speak to the driver author before I pass them on just to make sure he is OK with me redisting his work.

 

Is very simple to do. Keep meaning to do it myself but other things get in the way of me doing it

 

 

[admin]

Hello all, new to BYE and this forum.

 

Just tried out my Stellarvue SV80 last week in the backyard and quickly discovered that I probably need a motorized focuser as mentioned above (I drive the mount/DSLR via a 65 ft USB cable so I can stay warm inside).

 

So what is the actual recommended hardware for this?  Most of my Google searches found equipment in the near $500 range for this.  Are there less expensive/possibly DIY solutions for remote motorized focusing?

 

Thanks,

 

Felix

 

I'm also a dealer for MoonLite focusers... but they are not cheap <_>

 

Any ASCOM compliant focuser should work.

 

Regards,

[fjeske67]

Hi Not done it myself but you can use a Stepperbee kit with some rubber friction wheels which will work.  ...

 

This seems to be a UK-based product and I'm near Chicago so probably will be out of reach.  You have pointed me in an interesting direction, however, thanks.

 

 

[fjeske67]

Hi Not done it myself but you can use a Stepperbee kit with some rubber friction wheels which will work. ...

 

So I've decided just to jump in and bought a Arduino Uno board with a Motor Shield to control a small 12V stepper motor.  That plus some small friction wheels should be enough to drive the focus knob.  So far, I'm out $80 if this doesn't work.

 

I'm planning on driving the axle of the (removed) fine focus knob directly by attaching a friction wheel to it.  Is that what most do, i.e., vs. the coarse knob?

 

Have to wait for some of the hardware to arrive but might have something working after Christmas.

 

 

[admin]

Awesome, keep us poste onyour progress once you get the Arduino working

 

Clear skies,