Pulse Drip
Interactive installation originally developed for Urdaibai Art 2012 in which the public can water the lawn at the Torre de Madariaga using a water hose with a heart rate sensor built-in. To participate, visitors take the hose wherever they want to water: by putting their index finger on a tiny sensor on the spray head, his or her pulse is detected and an automated electromechanical valve controls the water flow to match the beat of the participant's heart. The spray head is a custom-made handle with a built-in heartbeat sensor, a rechargeable battery, a radio transmitter and an Arduino processor.
Source: Rafael Lozano-Hemmer http://lozano-hemmer.com/pulse_drip.php