As reported by [arstechnica]:

I've talked a bit before about mechanical musicians such as Wintergatan with this custom instruments, and Algoraves. Now another technical musician has surfaced named Moritz Simon Geist, who builds his own musical robots. You can listen to one of his techno pieces called Entropy [here], in it he uses a number of custom robotic instruments such as a Futuristic Kalimba, Pnumatic Hihat, Drone Guitar, Hard drive snare/clap, and actuator glasses. You can watch a behind the scenes where he goes into detail on the different instruments he's constructed [here]. There's also a further presentation Geist did at Red Bull Music Academy [here], and another for FACT Magazine [here] where he further discusses his robotics music.