I have to built a electric wheel chair for my father. Does any body has built ?
I used to do the opposite Sanjiv.....Turning electric wheelchairs into childrens toy cars.
Speed controllers are very cheap nowadays as are the motors etc from electric scooters.
There is a yahoo group for an open source speed controller.....as with all yahoo groups it's hard to follow!
4D type would be my first choice of controller as possibly they have one which can be controlled by a joystick.
Sad to hear your father needs one.....Sounds a good project though!