I was watching the contractor plow snow from the parking lot, onspot chains flailing away under the tyres, thinking how much I'd like the functionality for the drive home - at least for that unexpected patch of black ice - packaged into something that would fit onto a car. Nothing on the market fits the bill - resin sprays don't work quickly enough, retractable studs aren't realistic, and I'm looking for something more effective than winter tyres in the very lowest friction conditions. Months later, I think I have an idea for something for a 1000kg vehicle, that can add grip on snow & ice without stopping or compromising dry-road grip.... Attached to the wheel rim is a new rotating surface attached to the wheel, angled obtusely to the road and clear of the tyre by about 3cm, enough to allow the tyre to flex. Distributed around the perimeter are twenty or so arms that are deployed under the tyre, and retracted from it, electrically or pneumatically. The arms are made to be flexible vertically (so as to flex in conformity with the tyre), but rigid laterally and longitudinally. They would be surfaced with the high-tech textiles used on fabric chains and/or metal chains and/or studs. They would work best mounted on the inside of the wheel, where they would not interfere with extremes of dry-road cornering. This would bring clearance issues, but surmountable ones. The travel of the arms would determine space requirements - rotating around an axis could be a lot more compact than traveling along a linear one. Proposed as a complement to winter tyres, not an alternative. Activation only allowed by ABS and slip control systems - that are mandatory on new cars in 2011 - to restrict use to appropriate moments. Minimal weight and cost for the target of a safety enhancement that can be deployed on a moving vehicle. Noisy (when deployed) and expensive, but less so than accidents. Might even work on the front (steered) wheels.-- sstvp, Mar 07 2010 Onspot Automatic Tire Chains http://www.onspot.com/Developed in Sweden in the 1970's. ONSPOTS are designed to fit vehicles from 1/2 ton pickups to class 8 tractor trailers, both with and without air brakes. ONSPOT kits for vehicles without air brakes include a 12 volt air compressor and holding tank. [jurist, Mar 08 2010] All that and some paragraph breaks and you could be in business.-- normzone, Mar 08 2010 I used to think of stuff like this, back in the days before purchasing real snow tires. A set of blizzaks made my car UNSTOPPABLE.-- AutoMcDonough, Mar 08 2010 It's actually the stopping/steering that bothers me; the going part I've never had a problem with, including a winter in Switzerland where road salt is banned. Bought the Blizzaks already - still looking for something to enhance their capabilities, on the very most slippy ice.-- sstvp, Mar 08 2010 Sorry to say Ambulances already have this system. Automatic tire chains, google it.-- Arcanus, Mar 08 2010 Seen the automatic chains, referenced them in the opening sentence. I'm envisaging something similar in effect for a car, with its considerably smaller wheelarches, independent suspension, etc. And, I think this layout might fit and work on the front wheels.-- sstvp, Mar 08 2010 Yeah, but still no paragraph breaks.
Please, please, paragraph breaks. I think I might like this idea, but I can't tell.-- normzone, Feb 15 2011 I think that such a system would seem more possible with an illustration. The "notion" is well baked with many applications for large trucks but for other applications the art has not found application. If you have new art, make some art for us.-- WcW, Feb 16 2011 random, halfbakery