×

INDI Library v1.9.8 Released (29 Sep 2022)

Bi-monthly INDI Library released with new drivers and bug fixes.

Astrohat - An open hardware RPi Hat for astronomy equipment

  • Posts: 73
  • Thank you received: 8
Looks great. I was trying to consider what I have that might draw more than 3 amps. Maybe my camera at 100% cooling or a dew heater?

I think I need to test it and find out. :)
2 years 10 months ago #46275

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

  • Posts: 39
  • Thank you received: 38
The channels in pairs can draw 6A combined. Which means that in theory you could get e.g 5A in Channel A and then 1A in Channel B and still be OK. I guess we will have to make this somehow visible on the interface too (and on the case?)
2 years 10 months ago #46279

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

  • Posts: 166
  • Thank you received: 3
Wonderful idea!

I was wondering if something was available the other night as I came inside with my arms full of wires, cables, and power adapters for the various bits and pieces attached to my scope. Good luck on this!
2 years 10 months ago #46287

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

  • Posts: 39
  • Thank you received: 38
I am adding a connector exposing a serial port, for another peripheral. GPS is the prime candidate for that since there are many cheap serial (TTL) modules out there. (thanks to drone racing! :P)

Any other ideas? Features you would like to see?
2 years 10 months ago #46293

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

  • Posts: 1067
  • Thank you received: 137

Actually I think you have covered pretty much all of what is sneezed on a typical imaging set up, and what you would get on a commercial power hub, apart from maybe an output for a motor focuser..but with the units around now that have the controller built in to the motor housing, it’s probably not needed....
So all good, I would certainly buy one if you produced a few, along with a case for the lot... :)
Stellarmate OS on Raspberry pi4b
Skywatcher EQ8 pro, on steel pier
Takahashi FSQ85, FS60cb & Meade 8” SCT (de-forked)
Starlight Xpress SXVR H18, SXVR M25c, Lodestar x2 Guide Camera
Pegasus Ultimate Hub V2 for all USB & Power
Pegasus focus motors on all scopes
2 years 10 months ago #46298

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

  • Posts: 1275
  • Thank you received: 221
Oh this is promising. A dedicated astronomy HAT. Love it.
I ended up cramming GPS, RTC, Motor controller and a power supply board (Docker Pi) within my case. So if there is anything worth adding, I would say GPS, RTC and 5V@4A power to the Pi is what's most useful.
For motor control I installed the Adafruit motor HAT. But the Pololu A4988 controller is arguably better with higher supported PWM frequencies.
INDI/KStars on Raspberry Pi 4, 4gb
Raspbian Buster with AstroPi3 script configuration
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG/ASI120mm @280mm Guide Scope
PHD2
Waveshare Stepper Motor Board - DIY Focuser
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
2 years 10 months ago #46306
Attachments:

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

  • Posts: 1067
  • Thank you received: 137
Whatever is decided, it needs to be able to have the option of cooling the rpi, as with the rpi4 it gets very hot..so would need the room for a fan or at the very least a large heatsink... :)
Stellarmate OS on Raspberry pi4b
Skywatcher EQ8 pro, on steel pier
Takahashi FSQ85, FS60cb & Meade 8” SCT (de-forked)
Starlight Xpress SXVR H18, SXVR M25c, Lodestar x2 Guide Camera
Pegasus Ultimate Hub V2 for all USB & Power
Pegasus focus motors on all scopes
2 years 10 months ago #46324

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

  • Posts: 39
  • Thank you received: 38
Thanks for the suggestions!

I just pushed a new version on the repository and added the following:
- An external TTL connector for connecting a GPS module
- A RTC complete with battery
(here is a pic with the connector and the RTC)


As for the rpi supply the board has a 5V@3A power supply integrated.
Motor control is a bit of an overkill at this point imho, mainly because most of the newer focusers have the control integrated, but please let me know if you feel this is a showstopper.

@AstroNerd: regarding cooling, indeed it will be an issue. we will have to see once the first dev board arrives how we can accommodate a fan or a heatsink.
The following user(s) said Thank You: AstroNerd
Last edit: 2 years 10 months ago by Pierros Papadeas.
2 years 10 months ago #46331
Attachments:

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

  • Posts: 1275
  • Thank you received: 221
Amazing work.
Motor control is by no means a show stopper and certainly exceedingly difficult to include, that's why I didn't list it among the most useful features. However spare 5V and 12V headers with reasonable amperage supply and some filtering to power a stepper motor board one might add would be appreciated. I had to use a mini-buck converter stuck beneath the power board to power mine, (Follow the white power wires in my previous image).

As for anything else. Maybe an on/off switch. For cooling the Pi4, a 30mm fan is quite adequate in my experience, but I also have heat sinks installed. Regrettably it would monopolize a lot of space. As for GPS I am not very familiar with the TTL drone modules, are there options available that allow for an external antenna? I highly recommend supporting modules with a uFL socket for external antennas.
INDI/KStars on Raspberry Pi 4, 4gb
Raspbian Buster with AstroPi3 script configuration
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG/ASI120mm @280mm Guide Scope
PHD2
Waveshare Stepper Motor Board - DIY Focuser
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
2 years 10 months ago #46339

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

  • Posts: 881
  • Thank you received: 419
If the goal is to power everything through this, I'd worry about the current draw of a mount while slewing. I'm pretty sure I've seen my Atlas Pro draw 4 or 5A, but just for a short while.

USB outputs might be nice, but I suppose one could just connect a powered USB hub to this hat.
AP1100 & Orion Atlas Pro, WO/ZS105 w/Moonlight V2 focus, GSO RC10 w/RSF focus
ZWO ASI1600, Astronomik Filters, ST80, QHY 5L-IIm.
KStars/Ekos/Indi on NUC10 & RPi4 w/SSD -- Ubuntu
Projects: Greedy Scheduler, Terrain, Polar Align, Analyze, Linear Focuser, SEP MultiStar & GPG Guide, FITS autostretch.
2 years 10 months ago #46343

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

  • Posts: 39
  • Thank you received: 38
That sounds a lot, my EQ6 fully loaded barely passes 2A while slewing. In any case 6A per channel should be OK as long as the neighboring channel (with which they share the load) is on less than 0.5A (they share 6.5A rating)

I plan to do some extensive testing on the loads to confirm the design assumptions.

There is no way to get USBs through the GPIO header of the RPi, so that leaves you with the option to sacrifice one rpi port and put a hub. It makes little sense to integrate functionality in this hat unless it can be supplied through the internal GPIO header.
2 years 10 months ago #46344

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

  • Posts: 39
  • Thank you received: 38

Since we are going for an aluminum case, the antenna needs to be external. It also allows for flexibility of placement for the whole system. Having an external thing though got me thinking.... why not get the GPS completely external (IC + Antenna) and thus save on internal space (since we are already packed) and also allow for a possible usage of the TTL (serial TX/RX, VCC, GND) port for something else (in case someone does not want the GPS). Such GPS modules are cheap and look like this . Makes sense?
2 years 10 months ago #46345

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

Time to create page: 1.094 seconds