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Canadian Man Invented a Wheel That Can Make Cars Move Sideways (nationalpost.com)
An anonymous reader writes: Canadian man William Liddiard invented a wheel that allows vehicles to move sideways. "True all-way drive for anything with wheels," Liddiard says in an online writeup for his successful prototype of "omni-directional" wheels. They consist of a specialized roller-equipped rim that can move horizontally and a tire that is rounded like a donut. "This is a world first bolt-on application for anything with wheels," wrote Liddiard. "Now you can drive in all directions, and turn on the spot, when needed." His demo video titled "you've never seen a car do this...," has received more than 1.1 million views since it was uploaded on May 10th. The wheels are a "proof of concept" prototype right now, but Liddiard says the design would allow them to be made as durable and safe as standard automotive wheels. Omni-directional wheels are nothing new, though they are typically only used in wheelchairs, robotics and other small-scale applications. Honda Motor Co. debuted an omni-directional wheel at the 2009 Tokyo Motor Show, but it wasn't for a full-sized car -- it was for a Segway-style mobility device. "My wheel can hold ten times more than the other [wheels], while maintaining speed," Liddiard told Postmedia in an interview earlier this year. He's currently trying to sell his invention to a major tire or automotive company.
Unfortunately, if he thinks ' the design would allow them to be made as durable and safe as standard automotive wheels' them he has a nasty surprise coming.
Of course technically he is probably partially correct - the rims would post no problem.
However the tyres themselves? Not a chance, sorry.
Standard modern tyres combine a lot of technology to make them work as well as they do in griping, and most of that technology basically results in them not having a round cross section. The main width of the tread is close to flat, the sidewalls and base contain strong reinforcing bands, the bead carries large loads and the tread depth varies greatly from the center to the edges - all of this contributes to their effectiveness.
His 'invention' required the tyre to return to being a true 'doughnut' torus shape, which is a TERRIBLE shape for a tyre if you want any traction, as the contact patch is tiny. His invention also requires the torus to rotate on itself, placing huge stress on the inner and outer surfaces as it rotates sideways, which will result is high wear and low lifespan.
Basically, sorry but it is a non-starter for anything outside short lifespan, low load and low speed applications, and problem that is already well solved with sidewinder/mechanum 'tyres' which are a group of cones, and suffer for less issues than his system would (although speed is still a major issue, and traction a medium one)
Still, the media will love it, and people will 'wow' at the example video. A set of car wheel skates/dollies let you push a car around like this at low speed quite easily already, and have been around for a long LONG time - and are about as practical.
How do the rollers get power, how does the driver control the roller speed and direction, what kind of wear and tear does the tire experience when it is twisting like a smoke ring, will the tires slip on the rollers when the brakes are applied, and what's to keep the tires from coming off the rollers at high speeds or while braking? It sure seems to be adding a lot of moving parts to a simple, proven design just to make it easier to park without having to change the way the wheels are mounted to the car. It looks cool, though.
I don't understand exactly how these tires work, but having wheels with integrated rollers so that you can move sideways is a pretty old idea,
So, you are saying this is not forward progress, its more sideways progress?
A forklift you say?
This is what "I don't understand the problem" looks like.
The stress on that rubber when it's going in all directions is phenomenal. You're then going to expect it to drive at 70mph forward for hours at a time.
It's "cool" but it's totally impractical and unworkable. Conventional rubber tyre inner tubes are covered with a real tyre (made of steel, rubber and all kinds of layers) for a reason - the inner rubber is intensely fragile and doesn't take kindly to exposure and/or to lots of movement. It certainly won't take kindly to you sliding over stones laterally.
You are literally going to pop your tyres every few hundred miles of use. And as others have pointed out the complexities involved (in braking a tyre like that under extreme stress - 70mph to standing - it's just going to want to slip) mean that it's expensive, untested and impractical beyond belief.
And, I'm sorry, but this doesn't solve parking problems. It creates them. Idiots can park this in a space next to a conventional car making it almost impossible to get back out with a standard steering setup. Until everyone parks sideways, for the cost of a couple of inches of parking space each, it's just liable to misuse.
And I bet this "invention", brought to market and passing safety tests, will a) never appear, b) cost more than you could ever get by shrinking parking spaces by that fraction of space that it "saves".
Omnidirectional wheels are not new (1949 german parent).
What is probably new here is that the wheel surface is not a discontinuous set of smaller wheels - it's a toroidal tire that can rotate on the in-out axis. This requires the surface to stretch considerably and is probably not compatible with the requirements for car tires. This has real applications, but standard passenger cars are probably not one of them. This car demo is, however, a great way to attract attention and, hopefully, investment. A forklift just doesn't have the same dramatic effect.
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
Every year during the first couple of snowstorms you see cars (trucks and buses) do that. Mind you it's not intentional.
It's completely flat, it will have no "grip" to the ground.
This is a common misconception: flat tyres actually grip the ground better than tyres with a tread because they have a larger surface area in contact with the ground which generates more friction. This is why Formula 1 cars have flat tyres when racing in dry conditions. The tread is there because in wet conditions you need channels to get rid of the water between the tyre and the road when travelling at speed otherwise you hydroplane. So the tread is not there to increase grip but to get rid of water and as these tyres are now they will not grip well at speed in wet conditions but they will actually grip better than a treaded tyre in dry conditions.