[Grbl_Esp32 PR#94] Added wall plotter support

#1 – bdring 于 2019-02-19

I am very interested in adding kinematics to Grbl_ESP32, but I would like to do it in the cleanest, most modular and extensible way.

I prefer not to have multiple #ifdef MACHINETYPE statements in the core files of Grbl. I would prefer to have a single #USEKINEMATICS statement and define the kinematics elsewhere.

Do you think that makes sense? I have not looked at it in a while, but I thought LinuxCNC used a nice way. All machines use kinematics, but simple Cartesian machines use “Trivial” kinematics where x,y, and z where returned unchanged.

http://linuxcnc.org/docs/2.4/html/motion_kinematics.html

#2 – rognlien 于 2019-02-19

It think that makes sense, yes!
The core files are already very large. I think it would be nice to separate the kinematics into separate files. Probably for CoreXY too.

something like corexy.h, vplotter.h etc.?

I have very little experience implementing anything larger than the most trivial Arduino sketches in C/C++ (I come from the Java world), so I am not sure how to go about structuring it.

Also, how far are you willing to diverge from “standard GRBL”?

#3 – bdring 于 2019-02-20

Ill take a look at it.

BTW: What wall plotter design do you use?

#4 – rognlien 于 2019-02-20

We made one at work during a couple of hackdays. It consists of two Nema17 steppers, mounted on the top corners of a whiteboard with gt2 belt and a 3d printed gondola with a hobby servo. We are using a Rumba+ board and Makelangelo software to run it. It works well, but it would be very nice to make it more autonomous, so the wifi+SD-card capabilities of the ESP32 woul be great!

#5 – rognlien 于 2019-02-20

Here is a short video (2x or 4x speed, I think)
https://youtu.be/wLqPc_lA5t4

#6 – ewidance 于 2019-10-24

Bart, I know GRBL ESP32 is already huge, and i guess you would like to implement kinematics in a more global method (and probably is separated files to minimize memory imprint). But since proposed code is very small, it should be really interresting to add it now, even if it’s needs refactoring later to separate kinematics implementations… My 2 cent :)…

#7 – captFuture 于 2020-08-09

Is this still alive? I am currently looking at some possibilities for wallplotter support directly in grbl. @rognlien do you have further documentation of your configuration? I am missing things like motor distance, initial y, do you reset coordinates before starting and if you are sending coordinates in absolute or relative mode.
(I flashed the fork and it was behaving strange on my hardware setup)

#8 – rognlien 于 2020-08-09

@captFuture
No, not really, I am afraid. But it would be great if someone could help figuring it out. I did not really manage to get any reliable results with my code.