For those black-ice conditions where even the best winter- tires aren't good enough....

Tire studs have always been installed at 90 degrees to the rotation of the tire. I'm suggesting they be installed at 45 degrees to the surface, their surface normally running flush with the tire. When necessary, the studs would be rotated within their housing [by just a few degrees, and NOT screwed in or out]. In doing so, they would rotate on that 45 degree axis, so that half of their surface would rise above the tire tread, presenting an extra edge to the road surface.

Since they would only meet the road surface very occasionally, there's no concern about wear to road or the tyre stud.

I think the best way to make them rotate would be electrical.
-- sstvp, Apr 12 2013

perhaps they could be activated pneumatically by tiny little air bladders under the studs, activated by a wi-fi signal operating a solenoid that dispenses compressed nitrogen from a cannister affixed to the wheel.

I'm sure tire companies will get right on it.
-- whlanteigne, Apr 12 2013


The problem with having anything raised proud of the tire's contact area is that it will be worn down flush relatively soon. Also, this idea would present less overall contact with the road surface, not typically a good thing.

So, // For those black-ice conditions where even the best winter- tires aren't good enough.... //

...slow down.
-- Alterother, Apr 12 2013


//slow down// <channelling Rev Jim>

Foorrr thooossse blaaack-iiice connndiiitionnsss....

/<cRJ>
-- AusCan531, Apr 12 2013


//Are you suggesting a matrix of dozens of solenoids inside the tire to actuate each individual stud? //

You wouldn't need a separate solenoid for each stud. Just put a spring and a magnet on each stud, then a large electromagnet on the axle to force each of the studs out when it's turned on. Still seems unnecessarily complicated and expensive though.
-- ytk, Apr 12 2013


Perhaps it could be done by adjusting the tire pressure. If the studs were attached to the "belts" that are buried in the rubber of the tire, and if the belts were less flexible than the surface rubber, then if the tire pressure goes down the tips of the studs would maybe stick out. Also, you benefit by having more surface area of tire on the ground. When the snow has been cleared, you pump up the tire pressure again, and the rubber, expanding faster than the belts, hides the studs. Of course, after some thousands of kilometers of wear, the studs will always be peeking through the rubber. Can't have everything....
-- Vernon, Apr 12 2013



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