ShadowRam Wrote:
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> Couldn't all the cons of a bowden be solved by a
> small light incremental encoder at the hotend?
>
> So many joints,
>
> I think the number of tolerances will add up, and
> I'm worried you will have a tough time getting 1mm
> accuracy at the tool end.
>
> Interesting project though, keep going!
Brilliant idea! That could easily be done. I am going to design something up and put it inside the effector but not worry about using it right away. (This reminds me of an XKCD where a guy asks for a USB port to be installed during a surgery. He argues the firmware can be updated later.)
Image may be NSFW.
Clik here to view.
I was worried about tolerances adding up. ...but... I built some parts and I am hard pressed to see any wobble. Remember that a lot of the ways that this bot can and will wobble don't really affect the separation distance that we are trying to drive. Rigidity is high along the arm plane but very bad normal to it. That is okay because a slight normal displacement doesn't really affect the driven separation. (Check back in a week or two and I should have a full assembly sans motors to check for rigidity.)
-------------------------------------------------------
> Couldn't all the cons of a bowden be solved by a
> small light incremental encoder at the hotend?
>
> So many joints,
>
> I think the number of tolerances will add up, and
> I'm worried you will have a tough time getting 1mm
> accuracy at the tool end.
>
> Interesting project though, keep going!
Brilliant idea! That could easily be done. I am going to design something up and put it inside the effector but not worry about using it right away. (This reminds me of an XKCD where a guy asks for a USB port to be installed during a surgery. He argues the firmware can be updated later.)
Image may be NSFW.
Clik here to view.
I was worried about tolerances adding up. ...but... I built some parts and I am hard pressed to see any wobble. Remember that a lot of the ways that this bot can and will wobble don't really affect the separation distance that we are trying to drive. Rigidity is high along the arm plane but very bad normal to it. That is okay because a slight normal displacement doesn't really affect the driven separation. (Check back in a week or two and I should have a full assembly sans motors to check for rigidity.)
