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Turning a wheelchair into an all-terrain powered vehicle was a simple challenge and one that proved to be very useful. For the first attempt I used a 26 inch wheel with a built in hub motor. The motor was controlled by an electronic circuit in the small blue box atop the handlebars which connected the throttle control to the motor. The batteries sat in the square frame that connected the front wheel to the chair.
The connection was achieved by attaching a bracket to the under frame of the wheelchair which the power section slotted into. A quick release lever would then be locked to secure the two halves together. This would allow freedom outside together with the ability to quickly return to the conventional wheelchair for a root round the shops or to grab a meal somewhere.
This version served well and was just the thing for trips out with the dogs but came into its’ own for our trips to Centre Parcs. The only drawback was the size of the front wheel. As well as making it a bit on the large size for transporting in the car, the motor could not provide sufficient torque to power such a big wheel up the steeper hills. On the plus side, the large wheel did provide plenty of speed with it tripping 20mph on a roadside speed matrix.
I stuck with the above design for a few years before returning the parts to scrap and redesigning with a smaller wheel and a more powerful motor. This time, the wheel would be driven by chain with the small motor housed in a casing above the wheel. The frame slotted into the original bracket in the same way as before but as the bulky battery compartment from before proved to get in the way of the rider’s legs, the battery was now located in the black box in front of the handlebar. This also provided a bit of extra weight above the front wheel for a better grip on the road.
In this form the chair really would go anywhere and at a speed to make the brakes feel rather inadequate. A change of gearing brought the speed down a bit and provided a bit of extra torque to conquer the hills. This is one project that hasn’t been recycled… Yet!