All-Terrain Tracked Wheelchair (Planetary Hub Gear Reduction)

grabcad

Here is my concept for a hand driven all-terrain tracked wheelchair. The Track assemblies are attached to a standard collapsible wheelchair frame. The hand wheels drive the input shaft of the Nuvinci CVT or Shimano Alfine 11-speed planetary hub transmission. These provide between 380% to 408% gear selection so the user is capable of eaisly turning or ascending steep grades in the low range, while still being able to maintain a decent speed on flat ground in the high range. The leaf spring suspension maintains a soft ride while providing a small contact patch in the center of the track assembly to reduce turning friction. The rubber tracks are the VTR-050 lightweight robot tracks from VercoTrack. Hopefully this tracked wheelchair concept will bring the fabrication cost down dramatically compared to my original Articulating All-Terrain Tracked Wheelchair Design so that it would be more reasonable for people to fabricate or purchase in the future.