In general, the more contact area its rubber tyres have with the road, the faster a vehicle can stop in an emergency. Lowering a tyre's pressure should increase road-contact patch size.

So the idea: (slightly) deflate rubber tyres to increase road grip during emergency braking.

Maybe, implement this with sensors to detect 'true' emergency stops (so you don't get flat tyres in everyday traffic) and some sort of automatic deflation (maybe even reflation) mechanism, maybe on a single pair of tyres.
-- sonam, Jan 31 2021

Car flotation airbag system Car_20flotation_20airbag_20system
Shameless elf-promotion [8th of 7, Jan 31 2021]

Under heavy braking there would be a lot of force deforming the tires. I don't think you would want to go further than the designed tread pattern. Also people do crazy things in panic so tyre change should be out of the equation.

Might help for a perfect set of conditions but this would not warrant the extra complexity and cost.
-- wjt, Jan 31 2021


As you brake harder, more weight is transferred to the front wheels (assuming you are travelling forward). This in itself will enlarge the contact area of the front tyres, since the tyre will deform so that the down force on the tyre is equalised over the contact area with respect to the air pressure.

A larger contact area from lower pressure also means there is less downforce per unit area of tyre contact area. So you may have a larger area in contact but you may also come closer to the point where you lose friction and start to skid.
-- pocmloc, Jan 31 2021


Why not just have an under car airbag, that instantly inflates and adds a massive amount of contact friction between the car and the road?
-- xenzag, Jan 31 2021


Loss of directional control. It's usually better to be able to brake and steer, rather than just brake.

But such a device would be useful if the vehicle went into water; there is, however, Prior Art. <link>
-- 8th of 7, Jan 31 2021



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