An emergency running system, even if it is fitted out with a permanent tyre-pressure supervision, should not however, be confused with a system which changes the tyre-pressure while driving. In this case, apart from the possible breakdown assistance, there are also a number of other functions. The air pressure in the tyres of any vehicle can be adapted to suit various driving conditions, e.g., the pressure can be slightly increased for motorway travelling. Driver intervention is also possible, e.g., to slightly decrease the pressure to suit certain conditions when driving off-road in a . As far as utility vehicles are concerned, one can, to a certain extent, influence the loading-height or adjust the overall height when driving under low-bridges.
In the Russian Trekol, famous for it's gigantic tyres and the respective adaptation system, although it's engine isn't (yet) up to standard, the tyres can be adjusted to low-pressure and it's comparatively low weight of 2,5 tons due to the fibre-glass cabin is exemplary. The tyres, with a pressure of approx. 0,5 bar, distribute the weight over the enormous contact surface so well, that in exhibition events, they have already driven over a person, just for fun. The person concerned stood up afterwards and happily walked away.
The prospect of very quick tyre-pressure intervention, e.g., adjusting only one side when cornering, or only the tyres on the front axle when braking, has not yet even been considered. A great but also complex system, which in all cases, would need a special wheel-hub construction. If the wheel-rim is not altered, the system can be recognised immediatly when the vehicle is rolling, by the somewhat vulnerable connection between the wheel-hub and the air-valve. 06/13