Buxbaum and Sperka show off the (shopping) cart of future, Oak Park parade July 4, 2015.
A Roman chariot did quite well with only 1 horse-power, while the average US car requires 100 horses. Part of the problem is that our cars weigh more than a chariot and go faster, 80 mph vs of 25 mph. But most city applications don’t need all that weight nor all of that speed. 20-25 mph is fine for round-town errands, and should be particularly suited to use by young drivers and seniors.
To show what can be done with a light vehicle that only has to go 20 mph, I made this modified shopping cart, and fitted it with a small, 1 hp motor. I call it the cart-of the future and paraded around with it at our last 4th of July parade. It’s high off the ground for safety, reasonably wide for stability, and has the shopping cart cage and seat-belts for safety. There is also speed control. We went pretty slow in the parade, but here’s a link to a video of the cart zipping down the street at 17.5 mph.
In the 2 months since this picture was taken, I’ve modified the cart to have a chain drive and a rear-wheel differential — helpful for turning. My next modification, if I get to it, will be to switch to hydrogen power via a fuel cell. One of the main products we make is hydrogen generators, and I’m hoping to use the cart to advertise the advantages of hydrogen power.
Robert E. Buxbaum, August 28, 2015. I’m the one in the beige suit.
The riders should wear a bicycle helmet, you can crack your skull pretty well if you crash at 20 mph.
Why would you invent such a vehicle to promote hydrogen power? Motorized shopping carts exist already, however a motorized wheelchair or mobility scooter design would be more fitting to demonstrate hydrogen power as range is more important to them. They have electric drivetrains already, all you need to do is add a hydrogen range extender to demonstrate your abilities. I’m sure people who own a motorized wheelchair would love to have a range extender.
I’m not totally sure why I made the cart instead of a wheel chair. Mainly, I suppose, because I didn’t think of it. I was in the middle of developing a very efficient, 1 hp, hydrogen recirculator to use with solid-oxide fuel cells; had already bought the motor, and wanted to be in a parade with something small that could go 20 mph. I suppose I had the vague sense that wheel chair users would be less-likely to want to go 20 mph, or want anything like 1 hp pushing them (I could be wrong). Besides, a semi-broken shopping cart was cheep: only $50. Hydrogen makes a great range-extender. How much range do you think folks would want on a wheel chair?