Astroberry Focuser with Adafruit Motor HAT

  • Posts: 434
  • Karma: 1
  • Thank you received: 69

Astroberry Focuser with Adafruit Motor HAT was created by Ihoujin

I'm starting this topic up as Kaczorek mentioned it would be prudent to start a seperate thread on this topic, with a shout-out to Christian for his modifications.
Regarding the development of an Adafruit version of the Astroberry autofocus driver. The Adafruit motor controller HAT appears to be an excellent alternative to the PiFace. Whereas the PiFace required 2 integrated boards to control stepper motors and is no longer produced. The Adafruit is an all in one solution at a quarter of the price and is still being manufactured. It also just came back in stock. IMHO an ideal DIY autofocus platform.
INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
1 year 10 months ago #15534

Please Log in or Create an account to join the conversation.

  • Posts: 544
  • Karma: 6
  • Thank you received: 204

Replied by Kaczorek on topic Astroberry Focuser with Adafruit Motor HAT

Indeed it's interesting piece of hardware. I'm waiting for it's available in my local store. As soon as I get it I can start with a driver. Unless somebody else will accept the challenge. In such a case I can help.
--
Radek Kaczorek
Astroberry Server | NEQ6 | Atik 460EX | Atik EFW2 | ASI 120MM
1 year 10 months ago #15571

Please Log in or Create an account to join the conversation.

  • Posts: 434
  • Karma: 1
  • Thank you received: 69

Replied by Ihoujin on topic Astroberry Focuser with Adafruit Motor HAT

I am currently getting parts together in advance. I have the motor, and the Adafruit board. Plus I modeled everything and am ready to 3D print the rest. Once I get those all done I can theoretically begin to test anything you have written.
INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
1 year 10 months ago #16230

Please Log in or Create an account to join the conversation.

  • Posts: 544
  • Karma: 6
  • Thank you received: 204

Replied by Kaczorek on topic Astroberry Focuser with Adafruit Motor HAT

The Motor HAT is already available in my local store. I gave it a closer look and found out that it supports Raspberry Pi model A+, B+ and Pi 2. Raspberry Pi 3 is not on the list. This means I'm not going to buy it but I can develop a driver for it anyway. Let me know when you have all parts altogether so there is a piece of hardware for tests.
--
Radek Kaczorek
Astroberry Server | NEQ6 | Atik 460EX | Atik EFW2 | ASI 120MM
1 year 9 months ago #16279

Please Log in or Create an account to join the conversation.

  • Posts: 434
  • Karma: 1
  • Thank you received: 69

Replied by Ihoujin on topic Astroberry Focuser with Adafruit Motor HAT

That's understandable. Indeed the website doesn't explicitly state the Raspberry Pi 3. But I suspect that is probably out of date information. I had to do a little searching to find information that suggests it is indeed compatible. As seen here. I am currently 3D printing parts as I am writing this. So I should be ready to go soon. Thanks again for time.
INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
1 year 9 months ago #16280

Please Log in or Create an account to join the conversation.

  • Posts: 434
  • Karma: 1
  • Thank you received: 69

Replied by Ihoujin on topic Astroberry Focuser with Adafruit Motor HAT

Hello Kaczorek. Great news here. I have finished assembling my 3D printed, stepper driven focuser and have driven it successfully with the example scripts Adafruit provides.
INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
1 year 9 months ago #16470

Please Log in or Create an account to join the conversation.

  • Posts: 434
  • Karma: 1
  • Thank you received: 69

Replied by Ihoujin on topic Astroberry Focuser with Adafruit Motor HAT

I tried to attach these before. But I think the files were too large.
INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
Last edit: 1 year 9 months ago by Ihoujin.
1 year 9 months ago #16471
Attachments:

Please Log in or Create an account to join the conversation.

  • Posts: 434
  • Karma: 1
  • Thank you received: 69

Replied by Ihoujin on topic Astroberry Focuser with Adafruit Motor HAT

RobJones wrote: Looks good - I want one!
Are you prepared to share the STL file for the motor box? And do you have a parts list, I'm going to give this a go!
Also; interested to know what the gearing you have gone for on your NEMA stepper motor gear box? 5:1 or c50:1 ?


I have a few more iterative improvements I want to make before sharing the STLs which I am happy to do. The design is custom made specifically for the old style Skywatcher rack & pinion focuser. As for parts list. I will put one together when I get the chance. The motor I chose was a NEMA 14 with 51:1 gear reduction.
If I were to start over from scratch I would have probably chosen a NEMA 11 with roughly half that reduction. It's a lot of motor, slow and lots of torque. A bit overkill. I also had to add an LM7805 linear power regulator circuit onto the free pads built onto the motor hat to convert 12V to 5V to drive the motor properly and make holes through the case of my Raspberry Pi for new port and power terminal for the HAT.
INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
1 year 9 months ago #16498

Please Log in or Create an account to join the conversation.

  • Posts: 95
  • Karma: 3
  • Thank you received: 19

Replied by wbirk on topic Astroberry Focuser with Adafruit Motor HAT

hi!
as a side product of my raspberry Pi based telescope control system TSC - github.com/selste/TwoStepperControl/wiki/TSC - i am developing a custom driver that interacts via SPI with the pi and consists of a arduino pro mini and DRV 8825 ... would that be of interest??? shoulde not cost much more than ~ 20 € in total ...
yours
wolfi
1 year 9 months ago #16504

Please Log in or Create an account to join the conversation.

  • Posts: 544
  • Karma: 6
  • Thank you received: 204

Replied by Kaczorek on topic Astroberry Focuser with Adafruit Motor HAT

Well done! So it's my turn now to develop the driver for it. I will keep you posted of the progress.
--
Radek Kaczorek
Astroberry Server | NEQ6 | Atik 460EX | Atik EFW2 | ASI 120MM
1 year 9 months ago #16505

Please Log in or Create an account to join the conversation.

  • Posts: 36
  • Thank you received: 5

Replied by RobJones on topic Astroberry Focuser with Adafruit Motor HAT

Do you measure/sense that the focuser draw tube is at its limits?
1 year 9 months ago #16610

Please Log in or Create an account to join the conversation.

  • Posts: 544
  • Karma: 6
  • Thank you received: 204

Replied by Kaczorek on topic Astroberry Focuser with Adafruit Motor HAT

Limits are preset in a driver i.e. pos 0 is starting inward position and 20000 is maximum outward position.
Sensing the limits would require additional hardware such as encoders or similar.
--
Radek Kaczorek
Astroberry Server | NEQ6 | Atik 460EX | Atik EFW2 | ASI 120MM
1 year 9 months ago #16611

Please Log in or Create an account to join the conversation.

Time to create page: 0.594 seconds