Kinematic Type confusion

fhoran

Hello All,
I am working on designing and building a large format 3D clay printer. I know it looks funky but there are reasons why this is the best motor setup, but I am unsure how to find materials that will teach me how to implement this frankenstein polar-core kinematics type on a Duet 3 6HC. This layout only allows for one motor position for each corresponding build plate coordinate location so I am hoping this isn't a ludicrous question.

I am not sure if I am misunderstanding M669 but there doesn't seem to be anything like this even though it isn't far off from many common crane designs.

I am posting in general because I was uncertain where else to put this post.

I embedded a schematic drawing of the proposed kinematics type, if a more detailed engineering rendering is useful I have a 3dm with all the parts in it. I am an arts student so my math is self taught and full of holes, apologies for any obvious mistakes.

o_lampe

@fhoran
The drive mapping command M584 allows you to define a rotary axis. In your case

M584 Y{driver number} R1

But it sounds too easy to be true...

dc42

@fhoran I can see a couple of options:

Define and implement a new kinematics type in RRF. There is a brief description of how to do this at https://github.com/Duet3D/RepRapFirmware/wiki/Adding-New-Kinematics.
Modify the existing polar kinematics class files https://github.com/Duet3D/RepRapFirmware/blob/3.5-dev/src/Movement/Kinematics/PolarKinematics.h and https://github.com/Duet3D/RepRapFirmware/blob/3.5-dev/src/Movement/Kinematics/PolarKinematics.cpp to support mixing of the R and Z motors by adding an additional parameter. I can probably help you with this.

fhoran

@dc42 Thank you so much for the fast response, I will start poking around in the .h and .cpp files to get a better handle on this today.

fhoran

@dc42 Hello, It seems someone else is working on something similar to this at the moment, any idea if they have any overlap?

https://reprap.org/forum/read.php?185,844273

I saw you there too, you help so many people!