It should be highlighted that right now “Kosmo the Recyclenaut” is still a prototype; it is a working model of the end product. This means it needs further development until it can be deployed as a completely standalone classroom kit.

The techniques, materials, the hard- and software used now are chosen for their accessibility. The prototype can be used as a research method and to test various iterations of the project before making a finished product.

Below you will find all details about the prototype. If you go to Kosmo info Infinity and Beyond, you will find more information about how the prototype can be turned into a working device.


The bins consist of three basic (IKEA) trash bins with a custom made lid that fits on top of all three. The height of the screens and the height of the bins have been specifically designed for children. The average height of a Dutch child between with the age revising six to nine is 129 cm so that has been taken in account with many design choices. The trash bins have a height of approximately 60 cm so the children are able to look at the hole from above and easily of make use of it.

The top corners of the lid are rounded so in case the child falls or trips and hits the bin it will not do a lot of damage to the child. Children will be playing around the installation and they should be able to do so without have to face the risk of injury. Next to that it is also aesthetically more appealing and therefore made out of one piece of wood.
To be able to make the corners, a pattern is cut in the wood with a laser cutter to make it bendable. The laser cutting machine could not handle a piece of wood bigger than 31cm x 61cm so we had to divide the lid in three parts. At the side of the lid is space for the 3wieler logo, elephant ears logo and the HKU logo, which are engraved with the laser cutter.
The holes for each type of waste have a different shape and are made as small as possible for the best possible waste detection by the sensors. To make it more clear what goes where, a sticker is placed above each hole that indicates the type of waste.
The lid is coated with a varnish and is sandpapered afterwards so it is easy to clean and splinter free.


Three ultrasonic sensors are placed at the back of the lid above each bin and are used for waste detection. The sensor sends high frequency sound waves with a transmitter, when this wave reflects on an object it creates an echo and reflects back. By measuring the time interval between sending and receiving the sound wave the distant between the sensor and an obstacle can be measured. When this distant is short, it means something is interrupting the sensors’ view so something has been thrown in the bin.
It is not possible to measure if the correct type of waste is thrown in the appropriate bin. This still depends on children’s’ goodwill, of which they have a lot.

The sensors’ input is sent through wires to an Arduino. An Arduino is a microcontroller, a tiny computer that processes the information given by the ultrasonic sensors. The Arduino runs a program that sends this data to the Mac Mini so the rest of the game can use it as input.

Behind the bins a long, thin box is placed. A screen and soundbar are mounted on top of it. The screen is centred at approximately 120 cm so the child does not have to force its neck in an unhealthy position when looking at the screen. The soundbar has been placed just beneath the screen to get the best possible sound. Inside the box the Mac Mini, the Arduino and all the wires are placed.
The electronics such as the sensors and the wires are as much incorporated in the design as possible so children will not be able to touch it. They will not be able to trip and the electronics will not get damaged.