Patent ID: 8666562

Claim:
A method for estimating a maximum friction available between a vehicular tire and a road surface, the method comprising: measuring road surface properties via a sensor engaged with a vehicle, to obtain a plurality of road surface properties measurements; classifying the road surface properties measurements with a computer device in communication with the sensor, and storing the road surface properties measurements and classifications associated therewith, in a database; measuring a state of motion of the vehicle and a state of the vehicular tire associated therewith via a measuring device engaged with the vehicle, each set of state measurements comprising a driving dynamics measurement, when the tire is subjected to a friction force allowing an estimation of a maximum friction between the vehicular tire and the road surface; estimating the maximum friction between the vehicular tire and the road surface for each driving dynamics measurement via the computer device, and storing each maximum friction estimate in the database in correspondence with one of the classifications of road surface properties measurements; implementing the maximum friction estimate as a current maximum friction estimate in relation to the computer device; performing subsequent road surface properties measurements via the sensor, until a change is determined by the computer device in the subsequent road surface properties measurements, classifying the changed subsequent road surface properties measurement, and storing the changed subsequent road surface properties measurement in the database; retrieving from the database a stored maximum friction estimate compatible with the classification of the changed subsequent road surface properties measurement, by correlating the changed subsequent road surface properties measurement with the stored maximum friction estimate within the classification of the changed subsequent road surface properties measurement, according to a compatibility selection criterion including temporal proximity to present, and at least one of geographical proximity and identity of a stretch of road comprising the road surface; and implementing the stored subsequent maximum friction estimate retrieved from the database as the current maximum friction estimate, until one of: a change is determined by the computer device in further subsequent road surface properties measurements performed via the sensor; and a subsequent driving dynamics measurement is performed via the measuring device, the subsequent driving dynamics measurement providing a subsequent maximum friction estimate better compatible with the classification of the changed subsequent road surface properties measurement than the stored maximum friction estimate.