# Pedrail Wheel -- Looking for the physical explanation

Summary:
What is the physical explanation behind the pedrail wheel?
What is the physical explanation behind the pedrail wheel (a.k.a the walking wheel). Someone said it "makes it's own road", but how does it allow a vehicle to climb stairs, navigate rough terrain etc.? I have looked all over the Internet and even visited a university library, but information on this system is limited. I am trying to learn the operative principle(s) underlying this mechanism.

https://en.wikipedia.org/wiki/Pedrail_wheel
http://cyberneticzoo.com/walking-machines/1900-pedrail-walking-wheel-bramah-j-diplock-british/

Would it be possible to fashion a simplified version of the pedrail wheel that fit over a regular tire?

Thanks!

anorlunda
Staff Emeritus
I'm not sure what you mean by operating principles. This is a case where pictures are better than words. Watch this video and then you can ask questions about it.

Mgt3
DaveC426913
Gold Member
Would it be possible to fashion a simplified version of the pedrail wheel that fit over a regular tire?
That sounds like an opportunity! i.e. if someone had solved this problem already, you wouldn't have an opportunity to make your millions by solving it yourself.

The device is simpler than it may look. Between the video anorlunda provided and the wiki age diagram, you can derive the operating principles. It's akin to a tank tread, but as short as possible.

I'm not sure what you mean by operating principles. This is a case where pictures are better than words. Watch this video and then you can ask questions about it.

Thank you! Is the wheel simply riding over the feet?

DaveC426913
Gold Member
Thank you! Is the wheel simply riding over the feet?
Not quite. The hub (which is attached to the axle) has a flat bottom that forces the bottom four or so feet into a flat, surface-hugging shape - much like the tread of a tank does.

I just realized - it is functionally equivalent to simply riding on flat tires! (And that is possibly the secret to making this a practical invention.)

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Not quite. The hub (which is attached to the axle) has a flat bottom that forces the bottom four or so feet into a flat, surface-hugging shape - much like the tread of a tank does.

What would prevent this from losing traction in mud and allow a two wheel drive tractor to go in places a regular two wheel drive vehicle could not?

Baluncore