Konrad Klapheck is a German pop-art/surrealist painter, favoring "ironic treatment of everyday mechanics." Below is some of his machine-focused work. I would imagine that the marching hammers in Pink Floyd's "The Wall" were inspired by Klapheck's paintings.Konrad Klapheck, Das Opfer (The Victim), 1989Konrad Klapheck, Der Krieg (War), 1965Konrad Klapheck, Die Fanatikerin (The Fanatic), 1979 Konrad Klapheck, no infoKonrad Klapheck, Der Mütterliche Vater (The Mother's Father), 1977