The Sphere-O-bot is a friendly art robot that can draw on spherical or egg-shaped objects from the size of a ping pong ball to a large duck egg (4-9 cm).

The kit is based on the cool original design of Evil Mad Scientist 

The Sphere-O-bot elements

kit elements


What you need to create this painting robot


  • cable wrap (optional but makes everything look prettier..)


The Sphere-O-Bot is a simple 2 axis drawing machine that can draw on most spherical surfaces. You can use it to decorate balls or eggs.  This design also features the regular JJrobots electronics (the same we have used in all our robots). So you can create this robot or any other just simply printing new 3D printed parts and uploading the appropriate code.

The original idea belongs to Evil Mad Scientist 

The frame was designed by Attila Nagy


The Sphere-O-bot is adjustable, and is designed to draw on all kinds of things that are normally “impossible” to print on. Not just eggs but ping pong balls, christmas ornaments, light bulbs, and (yes) eggs (duck, goose, hens…).

The Sphere-O-bot frame was designed by Attila Nagy and slightly modified by JJrobots. The pen and egg motors are high-torque precision stepping motors, and the pen lift mechanism is a quiet and reliable servo (SG90) motor.

It is easy to assemble in an hour or so, and only requires a couple of basic tools like miniature Phillips-head and flathead screwdrivers. You’ll also need a reasonably modern computer with an available USB port (Mac, Windows or Linux), plus internet access to download assembly instructions and necessary software (Inkscape)

.The onboard 16× microstepping driver chips along with the 200 step/revolution stepper motors give a combined resolution of 3200 steps/revolution in both axes. A universal-input plug-in power supply is included with the EggBot kit, as is a USB cable and one Sharpie marker.

Above: Wines + stars design
Above: Wines + stars design. Click on the image for more designs

The Sphere-O-bot is normally controlled through a set of open-source extensions to Inkscape, the excellent and free vector graphics program. You can create your own drawings (Above: Wines + stars design below) or use one from the existing repository.

Basic operation is much like that of a printer: you import or make a drawing in Inkscape, and use the extensions to plot your drawing onto whatever object you’ve mounted in the Sphere-O-bot . It’s all handled through an easy to use graphical user interface, and works cleanly on Mac, Windows and Linux.sharpies

The pen holder included with the Sphere-O-bot kit is designed to fit various art pens including Sharpie Ultra Fine Point pens. It can actually fit almost any pen of similar size.

pen holder

Assembly diagram
Assembly diagram

You can even fit a lot of things that aren’t pens.

The Sphere-O-bot is an open source hardware+software project. Originally from Evil Mad Scientist (very cool robots), we have adapted the idea to our electronics and ancillary elements. Software, designs and use is exactly the same. . Extensive documentation about the original EggBot kit is available here.


The Sphere-o-bot robot shares almost all of its parts and 100% of its electronics with the B-robot EVO, the fastest -remotely controlled- Self Balancing robot, the iBoardbot or any other JJrobot . Create your own B-robot with the Sphere-O-bot parts!

DIY Brobot
All the jjRobots share the same electronics and ancillary elements
Having fun with the Sphere-o-bot
Create your own designs






(thanks for the photos!)