The High Striker is a modern homage to the old-fashioned fun fair of the same name (in German: Hau den Lukas). The sledgehammer is replaced by motion sensors in your smartphone.
The whole installation is about 4 metres high and comes along with several motion-sensitive LEDs and a costly illustrated cover.
The core mechanism of the High Striker consists of a solenoid valve and an air compressor. The valve can be controlled by the associated web application where motion and acceleration of a device gets registered. It then releases air according to a strike's strength which responds to the velocity and accuracy of your hand's hammering movement. The subsequent escaping air boosts a small rocket within a transparent tube indicating the reached height of a strike.
The High Striker is a highly experimental project. The installation and its web application are powered by Node.js, AngularJS and Socket.io while a Raspberry Pi serves as brain of the whole unit. The Pi controls the opening and closing process of the valve which ultimately gets triggered by a user directly. This was a delicate issue we had to deal with.
Nonetheless, the feel of the game was a complete success: a successful strike’s detection and the valve’s opening occurs simultaneously. Thus there is no noticeable delay, exactly like physically hitting the High Striker with a conventional sledge hammer.