Fritz Fend was an aeronautical engineer. He was noted for designing Messerschmitt’s Kabinenroller (cabinscooter) KR175 and KR200 microcars, for co-founding FMR, the company that took over production of the Kabinenrollers in 1956, and for designing the FMR Tg500, a sports microcar based on the Kabinenroller. Fend continued his career as an inventor and designer after the KR200 ended production. Fend was working on another lightweight vehicle project shortly before his death.
After the Second World War, Fend, who had been a technical officer with the Luftwaffe, opened a workshop in Rosenheim, Germany. In 1948, he devised an invalid carriage in the form of a tricycle. The front wheel of the tricycle was powered by pushing the handlebars back and forth. Originally designed with bicycle wheels, it was redesigned with scooter wheels in order to make the carriage lower. Fend later made a version that was powered by a 38 cc (2.3 cu in) Victoria two-stroke engine.