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So, I've embarked on a winter project with my Dad. I wanted a chair that was a little more capable in rugged terrain...rugged meaning anything with a grade of more than 5° and bumps bigger than a gravel. Wheelchairs just aren't made for off-road.

So, lets make one that is.

We've decided to go with tank-like tracks for the wheels. These are made by the company Mattracks. They are designed to fit directly onto an ATV, basically as if you were changing a tire. They are sweet!

It is going to be powered by two, 24v electric motors. I found some on ebay that are 900 watts each, and they are only about 4 inches x 4 inches. That's an impressive amount of power to pack in such a small motor. They are designed to power electric scooters, but a pair of them should be plenty sufficient for what we are doing.

That makes the total vehicle power about 2.4 horsepower. (1 hp = 746 watts)

I found a pair of 12v deep cycle batteries also to go along with this. But, from my calculations, these two batteries will only provide about one hour of run time...and that's running the batteries dead. Not acceptable. And, not healthy for the batteries, even though they are deep cycle. So, we decided to mount an on-board generator powered by a small gas engine, basically making the vehicle a hybrid.

AlternatorAlternator specsAnother ebay purchase....I got a killer deal on a 24v, 70amp alternator. That is huge, like, Mac truck size, but it should be perfect for our needs.

Bike EngineFor the gas engine creating the power, I considered going with a go-cart engine...I have a few around. But, instead, settled on this neat little bicycle engine I found on ebay. This thing comes with everything you need to bolt it on a bicycle and make it gas powered. It is a 2 cycle engine, I wasn't thrilled about that at first, but it's nice because you can pack more power in a smaller size with a 2 cycle, and with it's efficiency, I don't think it will be anywhere close to a gas hog. It's rated power is about 3hp at 5000 rpm, max 5hp at 6000 rpm. That is just enough power to turn the alternator. (Alternator power: 24vx70a=1680 watts=2.2 hp) Perfect.

Now that I've got all the parts, let's put them together.

The tracks come with these perfect little 1.5 inch square holes on either side of the main hub. They will be perfect for mounting the frame. And, would you believe we had some scrap 1.5 inch square tubing lying around. I've checked with the company to make sure these points on the tracks can be weight bearing....they can, so, on with construction.