Here is a simple explanation of lobing error. I teach metrology and this is the explanation I give my students.

The TP2 system uses physical switch triggering. The lobing is the slight error caused by the differential in time from when the outer surfaces of the ruby contacts the part and the stylus moves enough to trigger the switch. Because of this error, it is important to run your programs at the same speed used for calibration, else the lobing error will change.

In a TP200, with strain gauge technology, this lobing error is all but eliminated. This is because the probe triggers when a certain amount of force is applied to the stylus rather than a differential of motion. This force can often be changed within the measurement software (it can in PCDMIS for Windows at least).

The drawback to a TP200 is they are very sensitive and cannot hold long styli. The B type TP200 is somewhat more rugged and is available from your local Renishaw rep (in Canada, that's us). The TP200 does require some modification to your system to integrate the control system for the probe.

If you really want fast, accurate scanning I would suggest an SP600 from Renishaw. This is a continuous contact probe designed for scanning and it is far more accurate than either the TP2 or TP200. It can also hold something like 600 grams of stylus.

Cheers

Jim York
Canadian Measurement-Metrology Inc.
www.cmmxyz.com