So far we have been through five major prototypes and dozens of sub-prototypes. It's been a long process but we finally feel like we are getting somewhere significant. We now have three final stages of the Hand Drive, one with a single double ratchet, one with three double sided ratchets, and one with planetary gears incorporated into it. Although we have gotten each design to a high level of functioning, we are still working and still trying to improve our designs.
In the big picture, one of our goals is to work towards a design where the planetary ratchets can be 3D printed instead of milled. We never want to lose sight of our goal to make the Hand Drive affordable and accessible for all. Wheelchair user statistics inform us that wheelchair users are very unlikely to have jobs and, partly as a consequence, are substantially more likely than the remainder of the population to live in poverty. At all ages, income levels for mobility device users tend to be low. If we can pull this Hand Drive off we can significantly improve the quality of life for many- at a price point they can handle, and with the personal satisfaction of building their Hand Drive themselves with their own specifications.