The cam device and the writing automaton designed Pierre Jaquet-Droz

A cam is a mechanical memory for a machine. It contains detailed and intricate edges to store complex actions. The edge of the cam turns circular motion into up and down or backwards and forwards motions. The writing machine, Writer, still survives. It was built in Switzerland by Pierre Jaquet-Droz. He successfully put 6000 mechanical parts inside the Writer’s body.