Can a green thumb make the difference? Using a Nature Metaphor to Communicate Sensor Information of a Coffee Machine

This article describes a novel visual metaphor to communicate the sensor information of a connected device. The Internet of Things (IoT) aims to extend sensing and computing capabilities to every device. A byproduct of this is that even domestic machines become increasingly complex and more difficult to understand and maintain.

We present a prototype of a coffee machine outfitted with sensors. The machine streams the sensor data, which are picked up by an augmented-reality (AR) application conceived as a metaphor from nature. The metaphor, BioAR, represents the status derived from the coffee machine sensors in the form of a three-dimensional (3-D) virtual tree. The tree is meant to serve as a living proxy of the machine it represents. The metaphor, shown by using either AR or a simple holographic display, reacts to user manipulation of the device.

A first user study validated that the representation was correctly understood and that it inspired emotional connection with the machine. A second study confirmed that the metaphor scaled to a large number of such devices.