Open Hardware robot - Rosmo - Looking for volunteer(s)

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Sam_uk
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Sam_uk »

Nice, I love it :D

I can't seem to get images working here, but I added some here: https://github.com/rosmo-robot/Rosmo_3D ... /Readme.md

At first glance, the only part I think might need attention is the motor/encoder holders. I love the concept of what you've done, but it's unclear how the encoder board would be added/held in place?
Bance
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Bance »

Couldn't find any details of encoder, so made pocket the same as the example given, it's in the Motor bracket.

Does need a channel for wires, would need to know direction?

For images just drag and drop into text entry box.
ENC.png
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Sam_uk
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Sam_uk »

Nice :)

The issue is that the encoder pocket needs to be _opposite_ the motor, on the same side as your mounting flange. We could cut the centre of the flange away I guess? Just need to make sure there is enough material to be structurally sound.

I think it could work if we lengthen the 'flanges' (is that what they're called?) between the motor mounts.This part:

Image

Lengthening them would make space for the encoders, we could then cut away enough of the 'flange' to make room for the encoder.

A nice side benefit of doing this would be that the central pin:
Image
would be wider and stronger too.

As we haven't done the wheels yet, maybe we can accommodate the extra width there? By just putting the motor further into the wheel?

These are the encoders: https://github.com/rosmo-robot/Magnetic ... SPI#readme

Image
Last edited by Sam_uk on Fri May 13, 2022 7:54 pm, edited 2 times in total.
Bance
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Bance »

Looks like I have to make a sandwich :lol: :lol: :lol:
Sam_uk
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Sam_uk »

:)

Just found this photo of the encoder/motor holder

Image

https://github.com/rosmo-robot/Rosmo_3D ... coder.jpeg
Last edited by Sam_uk on Fri May 13, 2022 7:51 pm, edited 1 time in total.
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Kunda1
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Kunda1 »

(You need to link directly to the image)

Code: Select all

https://raw.githubusercontent.com/rosmo-robot/Rosmo_3D/main/V2/images/encoder.jpeg
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freedman
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by freedman »

Just a thought about tracks; they are very inefficient for turning. How about making the idler/drive wheels with a couple grooves and use o-rings. Not sure what the environmental requirements are for the device, cat hair could be problem :) .

The o-rings placed around each wheel might also give a measure of traction from drive to track if that is a problem.
Bance
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Bance »

I'll need to see if I can get both encoders to be the same way up (for easier wiring,) but it's a start.....

I made it in two pieces for easier printing.The encoder board needs to be drilled?
rob.png
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https://www.dropbox.com/s/0nn6jsv5yfklb ... FCStd?dl=0
Sam_uk
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Joined: Sat May 07, 2022 11:16 pm

Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Sam_uk »

Looking great!

The encoders come with the mounting holes, they don't need drilling

Image

What's the best way to explode a model in FreeCAD? I've installed https://github.com/JMG1/ExplodedAssembly but can't work out how to use it.
Bance
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Re: Open Hardware robot - Rosmo - Looking for volunteer(s)

Post by Bance »

Sam_uk wrote: Sat May 14, 2022 9:32 amThe encoders come with the mounting holes
But they don't align with anything useful.
Sam_uk wrote: Sat May 14, 2022 9:32 amWhat's the best way to explode a model in FreeCAD?
For checking parts is probably best to make everything invisible, then go back select the item for inspection and make it visible (Space-Bar)
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