A method of determining the inflation pressure of a tyre on a moving vehicle

A method of determining the inflation pressure of one or more pneumatic tyres on a moving vehicle having a plurality of n wheels fitted with tyres characterised by performing a set-up procedure comprising, for a range of tyre inflation pressures including all the vehicle tyres at their scheduled inflation pressure and combinations of one or more tyres at a range of pressures below their scheduled pressure and for a range of vehicle speeds and driving conditions such as accelerating, braking, straight-ahead driving and cornering, deriving for each of the wheels a speed value (Cn) proportional to the wheel angular velocity, determining and saving the relationship of the set of set-up speed values to each related tyre pressure, and subsequently in normal driving monitoring at intervals of time the wheel speed signals of the wheels on the vehicle, deriving an equivalent set of normal driving speed values based on these monitored wheel speed signals, obtaining the associated tyre inflation pressures. The method may utilise a trainable information processing system such as a neural network to map the speed values onto the set of tyre inflation pressures. The method may particularly be applied to detecting a deflated tyre on a vehicle.