PlotBot: Difference between revisions

Latest revision as of 18:15, 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: tiny_turtle_plotter_CAD.FCStd

Modified parts typically have "new" in their name. Sorry if it's messy. First time FreeCAD.

3D-printed parts for original build
Different endstop microswitch
Different size roller and endstop
Roller ball
Roller ball
Wheels and tyres
Wheels
Wheel carriage
Stepper motors
Hacked pen lifter

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.

Pen lifter

One robot is equipped with a more precise pen lifter that utilizes linear motion bearings (LM8) on 8mm rods.

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

We've drawn a PCB that can be sent to a manufacturing house, but is also optimized for chemical or CNC etching!

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

Cutting copper boards
Chilling in a pool after toner transfer
Toner transferred
Copper etching
Board fully etched
Posing for a picture
Perfboards are a no-hassle option
Back side of a perfboard

Software

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

More pictures

omg somebody please take a picture of it drawing and writing

Robot coming alive
Robot skeleton
In action

@@ Line 6: / Line 6: @@
   |status=active
   |tags=hw
-  |shortdesc=Our Rostock
+  |shortdesc=Whiteboard drawing bot
   |created=2025-25-09
 }}
@@ Line 24: / Line 24: @@
 == Our modifications ==
-Our FreeCAD model is here:
+Our FreeCAD model is here: [https://codeberg.org/lubko/turtle-robot/src/branch/main/tiny_turtle_plotter_CAD.FCStd tiny_turtle_plotter_CAD.FCStd]
-https://codeberg.org/lubko/turtle-robot/src/branch/main/tiny_turtle_plotter_CAD.FCStd
+Modified parts typically have "new" in their name. Sorry if it's messy. First time FreeCAD.
-Modified parts typically have "new" in their name.
 <gallery>
+File:555688595 1215584740611888 2776984424721907890 n.jpg|3D-printed parts for original build
 File:Turtle-endstop.jpg|Different endstop microswitch
 File:Turtle-switch-ball.jpg|Different size roller and endstop
+File:Turtle-ball.jpg|Roller ball
 File:Drawbot-ball2.jpg|Roller ball
+File:Turtle-wheels.jpg|Wheels and tyres
 File:Turtle-wheels1.jpg|Wheels
+File:Turtle-carriage.jpg|Wheel carriage
+File:Turtle-steppers.jpg|Stepper motors
+File:Turtle-pen-lifter.jpg|Hacked pen lifter
 </gallery>
 === Endstops ===
 The microswitches come in different shapes and forms. We added extra prongs to the bumper ring to engage with wider range of microswitches.
@@ Line 52: / Line 55: @@
 Ones we had didn't fit. We adjusted the layers 1 and made different versions of the upper ring to hold them in place.
+=== Pen lifter ===
+One robot is equipped with a more precise pen lifter that utilizes linear motion bearings (LM8) on 8mm rods.
+== Control Board ==
+[[File:Turtle-bot-v3-pcb-back-etch.png|thumb|Traces can be drawn on copper laminate (cuprexit) with toner transfer technique and chemically etched. Negative printout for PCB etching: [https://codeberg.org/lubko/turtle-robot/src/branch/main/artifacts/turtle-bot-v3-pcb-back-etch.pdf turtle-bot-v3-pcb-back-etch.pdf]]]
+We've drawn a PCB that can be sent to a manufacturing house, but is also optimized for chemical or CNC etching!
-== Software ==
+Schematic: [https://codeberg.org/lubko/turtle-robot/src/branch/main/artifacts/turtle-bot-v3-schematic.pdf turtle-bot-v3-schematic.pdf]
+Fabrication notes: [https://codeberg.org/lubko/turtle-robot/src/branch/main/artifacts/turtle-bot-v3-pcb-fab-notes.pdf turtle-bot-v3-pcb-fab-notes.pdf]
-Arduino code: https://github.com/vranicka/PlotBot
+Negative printout for PCB etching: [https://codeberg.org/lubko/turtle-robot/src/branch/main/artifacts/turtle-bot-v3-pcb-back-etch.pdf turtle-bot-v3-pcb-back-etch.pdf]
-== Control Board ==
+<gallery>
-[[File:Turtle-bot-v3-pcb-back-etch.png|thumb|Traces can be drawn on copper laminate (cuprexit) with toner transfer technique and chemically etched. Negative printout for PCB etching: [https://github.com/lkundrak/turtle-robot/raw/refs/heads/main/artifacts/turtle-bot-v3-pcb-back-etch.pdf turtle-bot-v3-pcb-back-etch.pdf]]]
+File:630198759 1327012059469155 4819732943989781073 n.jpg|Cutting copper boards
-Schematic: [https://github.com/lkundrak/turtle-robot/raw/refs/heads/main/artifacts/turtle-bot-v3-schematic.pdf turtle-bot-v3-schematic.pdf]
+File:631316442 1327012126135815 8139523202493073450 n.jpg|Chilling in a pool after toner transfer
+File:640173458 1339273461576348 8523389435759424901 n.jpg|Toner transferred
+File:633395964 1327012302802464 3349586654434092500 n.jpg|Copper etching
+File:640446084 1339273764909651 2435820910506464661 n.jpg|Board fully etched
+File:640928983 1339273704909657 7028863716144500154 n.jpg|Posing for a picture
+File:Turtle-front.jpg|Perfboards are a no-hassle option
+File:Turtle-pcb1.jpg|Back side of a perfboard
+</gallery>
-Fabrication notes: [https://github.com/lkundrak/turtle-robot/raw/refs/heads/main/artifacts/turtle-bot-v3-pcb-fab-notes.pdf turtle-bot-v3-pcb-fab-notes.pdf]
+== Software ==
+Arduino code: https://github.com/vranicka/PlotBot
-Negative printout for PCB etching: [https://github.com/lkundrak/turtle-robot/raw/refs/heads/main/artifacts/turtle-bot-v3-pcb-back-etch.pdf turtle-bot-v3-pcb-back-etch.pdf]
-===  Gallery: ===
+== More pictures ==
-<gallery mode="slideshow">
+omg somebody please take a picture of it drawing and writing<gallery>
-File:20260119_145224.jpg
+File:20260119 145224.jpg|Robot coming alive
-File:555688595 1215584740611888 2776984424721907890 n.jpg
+File:555534763 1215584797278549 3519708831245411009 n.jpg|Robot skeleton
-File:555534763 1215584797278549 3519708831245411009 n.jpg
+File:PlotBot.jpg|In action
-File:630198759 1327012059469155 4819732943989781073 n.jpg
-File:631316442 1327012126135815 8139523202493073450 n.jpg
-File:633395964 1327012302802464 3349586654434092500 n.jpg
-File:640173458 1339273461576348 8523389435759424901 n.jpg
-File:640446084 1339273764909651 2435820910506464661 n.jpg
-File:640928983 1339273704909657 7028863716144500154 n.jpg
-File:PlotBot.jpg
 </gallery>