Otto Berning was granted its first Robot patent in 1934; a US patent was granted in 1936. The camera was originally intended to come in two versions: Robot I, without motor, and Robot II with a spring motor. Its release was delayed and already the first camera "Robot I" included its hallmark spring motor. The first production cameras had a stainless steel body, a spring drive that could shoot 4 frames per second, and a rotary shutter with speeds from 1 to 1/500th second. The camera used proprietary "Type K" cartridges, not the now-standard 35 mm cartridges introduced in the same year by Kodak's Dr. August Nagel Kamerawerk for the Retina. The camera does not have a rangefinder, as it was designed for use mostly with short focal length lenses (e.g. 40 mm) with great depth of field.