ODOMETER SYSTEM FOR A MOBILE APPARATUS
An odometer system for a mobile apparatus (1) is described. The odometer system comprises a distance determining device (2, 30) configured to transmit a beam of radiation (13) from a stationary measurement reference point (3) remote from the mobile apparatus (1) to a target surface (4) at the mobile apparatus (1) and to determine, from reflected radiation (15) of the beam (13) off the target surface (4), a measurement value of an instantaneous separation distance (D m ) between the target surface (4) and the stationary measurement reference point (3). The system further comprises data receiving means (7', 9) at the mobile apparatus (1) and communication means (7) for wirelessly communicating the measurement value to the data receiving means (7', 9) at the mobile apparatus (1). The data receiving means (7') comprises offsetting or zeroing means (10, 9) for identifying a reference start point (21) for measuring a travelled distance (Dt) of the mobile apparatus (1) along a path, and for determining the travelled distance (Dt), using subsequently received measurement values, with respect to the identified start point (21).