Abstract: System for estimating the speed of a vehicle by determining a first parameter based on the rotational speed of a first set of wheels of the vehicle, such as its drive wheels, and to estimate the speed of the vehicle (vestimate) using the first parameter, determining a second parameter based on the rotational speed of a second set of wheels of the vehicle, identifying any difference between the first and second parameters and from that determining the actual speed, indicating the actual speed and controlling the actual speed to a maximum.

Abstract: The present invention relates to an engine speed indicator for a vehicle, which is driven by a combustion engine. The engine speed indicator comprises a first indicator arranged to show the actual member of revolutions of the engine and second indicator arranged to show at which number of revolutions or within which range of number of revolutions a minimal emission of at least one emission gas is obtained from the vehicle during operation of the combustion engine. The engine speed indicator also comprises a third indicator which is arranged to show an emission level of the emission gas at the actual value of the number of revolutions. A driver can hereby drive the vehicle in such a manner that the emissions of emission gases are substantially minimal.

Abstract: The present invention relates to an engine speed indicator for a vehicle, which is driven by a combustion engine (4). The engine speed indicator comprises a first indicating means (1, 13) arranged to show the actual member of revolutions of the engine and second indicating means (7a-b, 8a, 14) arranged to show at which number of revolutions or within which range of number of revolutions a minimal emission of at least one emission gas is obtained from the vehicle during operation of the combustion engine (4). The engine speed indicator also comprises a third indicating means (8a, 15 which is arranged to show an emission level of said emission gas at the actual value of the number of revolutions. A driver can hereby drive the vehicle in such a manner that the emissions of emission gases are substantially minimal.