My PCBs arrived

and I would thank everybody for their help to get this going.

Hi,

OK, as title says I got my PCB, 8 different designs. Quality from my point of view look good for me. Nice finish and all holes and tracks look good.

So far I have checked them and found out I have some mistakes, bur being a rookie in this and being my first PCB design or layout or whatever it is called that is understandable. Maybe making to many PCB at the same time (but I needed them all at the same time) and I got mixed up as well as choosing the wrong footprints made me make the mistakes.

Instead of taking, as it was planned angled pin headers, I took straight pin headers for combining a horizontal and a vertical PCB and so the placement is wrong.

Also missed some measurements of placement.

Having physically the PCB in the hands one can analyze better the positioning of everything and get more experience for the future in order to avoid these mistakes.

Now I have enough material to redo them and order the second batch :slight_smile:

regards Rainer

When you need to match mechanical parts and measurements for boards and enclosure you may need to consider STEP model and exporting to check your models in a mechanical environment

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Hi maui,

Thanks for the tip and ¿ where do I get such a software ?

regards Rainer

freecad + stepup

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Thank You :slight_smile:

Hi,

After getting the first batch and seeing my mistakes I am reworking the whole enchilada now.

I have a question in regard if I am doing correctly the internal cutout for the boards.

After making the gerber files including drill file I go to Gerblook to check the board and have seen that Gerblook does not represent the cutout in a a free way as Gerbview does in KiCad.

¿ is my board correct and does the board producer make it according to Gerbview from KiCad ?

Thanks in advance and regards Rainer

Look at the 2 images

Gerbview in KiCad

Gerblook

more tools you can test this with…

That is true. gerbview in KiCad shows the solder mask as a negative, i.e. it shows where solder mask will be removed. Gerblook tries to show a more realistic image, and shows the solder mask as a positive image. Clearly, it doesn’t matter what solder mask is in a section of board that will be removed, so KiCad does not issue Gerber commands to remove it. gerblook apparently does not care about cutouts either, so shows soldermask in areas that will be removed.

The board is probably correct. The board producer will interpret the files you send, because cutouts aren’t specifically defined in Gerber files. The only way to be sure is to talk with your board producer.

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Thanks Joan Sparky and bobc

I just tested in PCB-Pool and it looks the same as in Gerbview in KiCad so I am confident I will get them correctly.

regards Rainer

Hi Everybody,

Well yesterday I got the second batch of PCB for my ongoing project. Everything went fine and as you can see the cutouts are perfect where I wanted to have them.

After I ordered them I got an e-mail asking me if I want a cutout or plated drill holes in one of the PCB. I did not get it until I saw the image they had attached to the e-mail. Looked at what happened and which I did not understand first why but then looking into my files I had added an old drill file with plated drill holes :confounded:

The smallest PCB is 10mm x 19mm :slight_smile:

Here is the look at the PCB using all the files in my folder and you can see it finished on the image above

All the parts fit mechanically where they have to. Now I am going to assemble the first prototype, check everything and finish the programming of the software for the Arduino Uno which is used in this hardware.

Thanks again for all the help I have got

regards Rainer

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Hi Everybody,

Well it was an exciting weekend soldering the first prototyp and yes it was a partial success. The PCBs all fitted nicely together and was interesting to see how this first project started to take shape.

Look at the images

and inside the aluminum enclosures it looks like this

On the left side is the sensor connected via the coloured cable to the control unit and from there the grey wire goes to the telescope mount.

The surprise came when I started to test the singe modules of the Arduino software and I encountered an uplaod problem. After consulting in the Arduino forum the problem could be solved. I should not have used Pin 0 and Pin 1 for driving some LEDs. So the solution was to cut the connecting pins from my board to the arduino and to relocate pin o and Pin 1 to other avalaible pins which I did using wire brigdes and from there everything went smooth.

Now the next days will be programming days until the hardware does what I want and that is controlling the mount in order to keep the sun n the center of the telescope.

Again I appreciate all the help I received here and it is really interesting to see such a thing from the idea to something that one can hold in the hand.

Thanks and regards Rainer

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A picture may be worth a thousand words, but NOTHING beats hardware!

Dale

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Thanks for sharing.
Using Pcbs for the end parts of the cases was pretty smart idea methinks!

Hi Sprig,

Well from what I imagined about how good the tolerances are when designing a board I said myself why not try it and yes it is amazing how well they did fit as well as the cutouts.

It saved me from producing aluminum parts and I was able to add some feet for the positioning onto the telescope

OK it was quite a lot of measuring and trying. As I wrote before the first batch had errors but that helped for the second batch and on the second batch everything fit perfectly.

A method for testing how the pieces fit together was to print out everything from KiCad in scale 2:1 on transparencies and then over a light table look at the fittings :slight_smile:

regards Rainer

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Hi,

Well I guess all of you who helped might be interested in seeing what my hardware does.

Finally I was able to do some real world guiding tests and here you can see them in a few videos.

In the next video you can see the drift I have and the Sun gets out of center of the camera. As my mount is not aligned against the celestial north pole this is normal.

In order to see the videos please use the password RSol

This happens in 20min https://vimeo.com/244270281

Here you can see the guiding and in some parts I moved the Sun out of the center on purpose to see how it goes back via the guider https://vimeo.com/244270196

regards Rainer

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Cool stuff.

Next step is to bump it up a notch by using an ARM based MCU, do image analysis of the telescope bound cameras live view to make it work for stars as well :wink:

Thank You. Well guiding on stars is a very different thing and we do it in a different way. We use either Off Axis guiders integrated in the cameras, On Axis guiders also directly looking into cameras or via a guding scope which is mounted side by side or Piggy Back and there are already existing software packages to do it. This software packages guiding on stars do not work on the Sun due to the high luminosity :slight_smile:

So far I ahve seen only one commercial Sun guider at a cost of US $ 700,00 made by HUTECH in California. Also I know about an Australian guy who made a Sun guider too but never heard again of it. A few years ago I made a 100% analog guider using OpAmps and resistors etc. etc.

Now with Arduino I have more control over the guiding. I am still in development as I want to add a User Interface.

regards Rainer

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For future mechanical prototyping: plot the boards to pdf, print, glue them to cardboard, cut, and you will have 1:1 real-life physical model.

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