We hope to create a three-speed gear hub with a reversed 1st and 3rd gear. Our hub will be based on modifications of readily available commercial parts and hubs.
Currently our design is based on a planetary gear concept. If the sun gear can be powered with the arm held in place, the ring gear can be attached to the output to achieve a 1:3 low reverse-gear ratio. Conversely, if the ring gear can be powered with the arm held in place, the sun gear can be used to give a 3:1 high reverse-gear ratio. The power source can then be coupled directly to the output to give the 1:1 forward ratio. https://cdn.instructables.com