Tandem is a mobile interactive installation built in collaboration with Assia Kraan. The installation could be found at
the 2011 edition of festival In Vervoering in Utrecht (NL) amidst singer-songwriters
and poets performing on small mobile stages such as horse carriages, caravans, cargo
bikes, and boats.
The tandem brings curious people together. You can only guess what the people on the
bike are experiencing. So, you and your friend also get on the bike, put on the
headphones hanging from the handlebars, and start pedaling. The rotation of the
wheel powers the installation that now starts playing music through the headphones..
in slow motion. When you pedal faster, the music becomes much clearer, and you
recognize the song!
The installation is built around a 1937 Gazelle tandem which is fixed in place on
rollers. The source of the music playing on the headphones is a Sony Walkman
cassette player controlled by an Arduino.
The Arduino determines the pedaling speed by reading the 6V AC current originating
from a dynamo attached to the rotating rear wheel. The music playback speed is
controlled by an algorithm that varies the average DC voltage applied to the
walkman’s motor using PWM signals from the Arduino.