| 摘要 |
A method is described for calibrating apparatus comprising a measurement probe (4) mounted on a machine, such as a machine tool. The machine is arranged to capture machine position data (x,y,z;70;80) indicative of the position of the measurement probe and the measurement probe is arranged to capture probe data (a,b,c;72;82) indicative of the position of a surface relative to the measurement probe (4). The measurement probe (4) is an analogue or scanning probe having a deflectable stylus (14). The first step of the method involves moving the measurement probe (4) at a known speed relative to an artefact (30;40,42) whilst capturing probe data (a,b,c;72;82) and machine position data (x,y,z;70;80). In particular, the measurement probe (4) is moved along a path that enables probe data (a,b,c;72;82) to be captured that is indicative of the position of one or more points on the surface of the artefact relative to the measurement probe (4). The path includes at least one change in the direction of probe movement that can be identified from the machine position data and the probe data. A second step of the method comprises comparing the machine position data (x,y,z;70;80) and the probe data (a,b,c;72;82) and determining from that data the relative delay in capturing probe data and machine position data (i.e. the so-called system delay). |
