it is…
a compact composting toilet with a garden attached to its back the toilet collects and composts human manures through the internal machinery, and use the compost to grow plants on the back of the toilet the toilet is compact enough to be placed in a bathroom in a normal apartment the toilet is environment-friendly. Does not need external water or electricity supplies to run.

In this instrutable, you will be guided to assemble a mechanical model of the toilet made from paper board.

Step 1: Download the Paper Model

This paper model will serve as a template for the lasercut model we will make later on. The purpose of this model is also to show us the inner mechanics of a composting toilet, specifically, how the biodrum works. This model (courtesy of Rob Ives) will create a 2:1 gear which is exactly what we need to make the biodrum rotate.

Step 2: Make the Paper Model

Once we've downloaded the paper model and printed it out on some card stock, we can now assemble our paper gear. As we assemble the gear, take notice of how each piece fits into each other, since this will be important to know when assembling a plastic version in the next step.

Step 3: Print a Lasercut Model

In order to print a laser-cut version of the 2:1 gear, open the paper template inside Adobe Illustrator and scale each part to fit the dimensions of the desired laser-cut model. Now you can laser-cut your Illustrator file onto a surface of your choosing.

Step 4: Make a Biodrum in TInkercad

In order for the model to look like an actual biodrum plus a crank, let's make one of the gears into a "biodrum". In Tinkercad, import a .stl file of one of the gears and extend it so the 3D model looks like a cylinder with jagged sides.