A method of determining distance travelled by an object

摘要

A method of determining the distance travelled by an object, with particular application to commercial vehicles subject to haulage levies, is disclosed. The method includes the steps of receiving a first distance signal and an independently generated second distance signal, determining a distance calculation coefficient based on the second signal, using the first signal and calculated coefficient to determine the distance travelled in a particular time period, and transmitting the determined distance value to a remote entity. When applied to a vehicle the first signal may be generated by a tachometer and the second signal may be obtained from a GPS device in order to calibrate the tachometer to produce reliable distance data. The remote entity may be a billing centre that converts the distance data into a corresponding road user charge for the vehicle.