This is my first post, having discovered this forum about halfway through my project. The craftsmanship and ingenuity of the folks here is stunning. After watching the many creative and well-executed solutions posted here I hesitated to share my own "non-hub drive" with such a crowd of master builders. But, here goes...
The build resulted from a challenge by my son, a former pro bicycle racer, and is purely for fun. Could I build an electric tandem based on actually pumping the pedals? Would it climb the steep hills where we live? The result of the challenge is Joules, who sits on the stoker seat and does all of the pedaling. The fun part was coming up with a drive linkage that would use human-proportional legs to pedal in a circle matching the pedal cranks. The linkage delivers force tangent to the crank circle through the whole pedal revolution. The kinematics of the result are interesting to watch. (Hope that as a newbie I can get a video to work...)
- Joules
- Joules1.jpg (125.98 KiB) Viewed 4023 times
- Getting ready for the first ride
- Joules2.jpg (179.59 KiB) Viewed 4432 times
- The linkages were the fun part
- Joules3.jpg (111.29 KiB) Viewed 3962 times
- More linkage detail
- Joules4.jpg (101.97 KiB) Viewed 3968 times
- 3 stage transmission from 2400 RPM at the PMG-132 motor to about 90 RPM at the cranks
- Joules5.jpg (136.47 KiB) Viewed 4008 times
you tube post: http://www.youtube.com/watch?v=HcW-VzpgcE8
I'd appreciate any comments/questions.
Regards, guys,
Carl
Truly awesome! 
much respect
