PlotBot: Difference between revisions

Revision as of 17:40, 25 March 2026

What is this

A whiteboard drawing bot project. We didn't design the thing, but we built a couple of robots. Along the way, we made modifications and learned a lot.

Among things we learned is that it's a perfect project to get start with robotics.

Here's where it comes from:

https://hackaday.com/2025/09/02/this-plotter-knows-no-boundaries/

https://www.niklasroy.com/robotfactory/

The above link actually contains everything needed to get the bot going. Below are adjustments for parts we had.

Our modifications

Our FreeCAD model is here:

https://codeberg.org/lubko/turtle-robot/src/branch/main/tiny_turtle_plotter_CAD.FCStd

Modified parts typically have "new" in their name.

Different endstop microswitch
Different size roller and endstop
Roller ball
Roller ball
Wheels and tyres
Wheels
Wheel carriage
Stepper motors

Endstops

The microswitches come in different shapes and forms. We added extra prongs to the bumper ring to engage with wider range of microswitches.

Roller ball

We used a larger furniture ball, which in turn means we had to make room in the parts in two lowest layer and make the wheels larger.

Wheels

The wheels were too small, possibly because our roller ball was bigger. They were also rubbing against layers 1 and 2, and appeared to be made for 5mm shaft in the stepper (our had 6mm). This has, of course, thrown off the geometry. a little.

We also had different size tyres.

Power banks

Ones we had didn't fit. We adjusted the layers 1 and made different versions of the upper ring to hold them in place.

Software

Arduino code: https://github.com/vranicka/PlotBot

Control Board

Traces can be drawn on copper laminate (cuprexit) with toner transfer technique and chemically etched. Negative printout for PCB etching: turtle-bot-v3-pcb-back-etch.pdf

Schematic: turtle-bot-v3-schematic.pdf

Fabrication notes: turtle-bot-v3-pcb-fab-notes.pdf

Negative printout for PCB etching: turtle-bot-v3-pcb-back-etch.pdf

Gallery:

Robot coming alive
3D-printed parts
Robot skeleton
Cutting copper boards
Chilling in a pool after toner transfer
Copper eEtching
Toner transferred
Board fully etched
Posing for a picture
In action

@@ Line 72: / Line 72: @@
 ===  Gallery: ===
-<gallery mode="slideshow">
+<gallery>
-File:20260119_145224.jpg
+File:20260119 145224.jpg|Robot coming alive
-File:555688595 1215584740611888 2776984424721907890 n.jpg
+File:555688595 1215584740611888 2776984424721907890 n.jpg|3D-printed parts
-File:555534763 1215584797278549 3519708831245411009 n.jpg
+File:555534763 1215584797278549 3519708831245411009 n.jpg|Robot skeleton
-File:630198759 1327012059469155 4819732943989781073 n.jpg
+File:630198759 1327012059469155 4819732943989781073 n.jpg|Cutting copper boards
-File:631316442 1327012126135815 8139523202493073450 n.jpg
+File:631316442 1327012126135815 8139523202493073450 n.jpg|Chilling in a pool after toner transfer
-File:633395964 1327012302802464 3349586654434092500 n.jpg
+File:633395964 1327012302802464 3349586654434092500 n.jpg|Copper eEtching
-File:640173458 1339273461576348 8523389435759424901 n.jpg
+File:640173458 1339273461576348 8523389435759424901 n.jpg|Toner transferred
-File:640446084 1339273764909651 2435820910506464661 n.jpg
+File:640446084 1339273764909651 2435820910506464661 n.jpg|Board fully etched
-File:640928983 1339273704909657 7028863716144500154 n.jpg
+File:640928983 1339273704909657 7028863716144500154 n.jpg|Posing for a picture
-File:PlotBot.jpg
+File:PlotBot.jpg|In action
 </gallery>