• The final prototype with an IKEA mat on top, Arduino Yun and loud speakers in the box

  • Sewing the base layer of the mat (conductive thread)

  • Affixing the top layer of the sensors (conductive fabric) - the middle layer is velostat and foam rubber

  • Multiplexing the input from the 30 pressure sensors with two multiplexer chips

  • Final prototype with Yun and multiplexers as a shield


Rainminder is not just your ordinary door mat that sits quietly in front of your door. When it is going to rain outside and you walk across it, it will sound like you are stepping into a puddle. It ambiently reminds you to take an umbrella with you. When it is going to be sunny, the mat remains quiet.
The project is an exploration into how everyday objects (in the smart home) can be augmented with digital information in the future.

The mat features 30 individual soft pressure sensors which are connected to an Arduino Yun. It detects when a person steps on the mat and where he or she places his or her feet. The Yun gets the weather forecast for the location and the current day from openweathermap and checks wether it is going to rain.

I made the mat and the 30 pressure sensors with conductive fabric and velostat and programmed the Yun to detect pressure and play random splash sounds accordingly when someone steps on the mat. To make the experience more realistic, the sound increases or decreases according to how hard or soft the person steps on the mat.

Short video of the prototype in action:

Initial sensor prototype (with cat content):

Rainminder was presented at the Mensch & Computer conference 2015 in Stuttgart, on BOSCH HMI Tech Days at BOSCH HQ Gerlingen as well as on World Usability Day 2015 in Berlin.

Category work
together with Henrik RieƟ, Martin Ecker and Peter Klein
Project reference on UID website

Year 2015