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3D precision probe, sensor for CMM and coordinate measuring machine.

This section discusses sevral frequently asked questions ragarding the Gannen Ultra Precision 3D tactile scanning series. Should you have any questions not discussed in the list below, dont hesitate to contact us.


Frequently asked questions

  • Why does the probe break?
  • The probe replaceable will only break due to faulty operator handling or control errors in the CMM. In the latter case damage to the workpiece is prevented by a break-off of the probe tip.
    A "break-away" mechanism can be implemented to prevent damaging the sensor. However this mechanism will decrease the uncertainty of the probe, increase it's mass and increase the risk of damaging the work piece (especially due to control errors). Contact us about the possibilities for implementing a break-away mechanism within the Gannen probe.
  • When does the probe break?
  • The probe replaceable will break, when the measurement range exceeds approximately 100 micrometers. The range of today's high accuracy CMM's varies around 7 micrometers. Breaking of the probe will therefore only occur as a result of faulty operator handling or control errors of the CMM. In the latter case damage to the work piece is prevented by a break-off of the probe. Should this happen the sensor needs to be replaced. A skilled operator at your company can easily replace the sensor in a matter of seconds.
  • What about hysteresis due to the piezo resistivity
  • In typical piezo resistive measurements a hysteresis of approximately 1% can be observed. This would mean a measurement deviation of 100 nm over a 10 micrometer measurement range! By implementing several measures we have been able to decrease this effect dramatically.
  • How sensitive is the probe to temperature?
  • Since the probe is designed to achieve an uncertainty in the nanometer range it is naturally sensitive to disturbances. As shown by the measurements with the Gannen probe the drift due to temperature effects is 10 nm or less within a typical low uncertainty CMM environment.
  • How do you know the probe sensitivity?
  • Due to the probe production process (etching and deposition) the sensitivity of the probe cannot be predicted with sufficient uncertainty beforehand. Therefore the probe is calibrated to establish the relation between the measurement signal and probe displacement. This calibration can be performed on the CMM itself or XPRESS Precision Engineering can calibrate it for you.
  • Do you have (high quality) images of the Gannen probe and can I use them?
  • Yes. We even have a high quality images section on our site where you can find high quality photos of the Gannen probe.
    You may use these images free of charge. We do however require that you mention the source of the image ('Photo courtesy of XPRESS Precision Engineering, www.xpresspe.com') and, if used online, a working link to www.xpresspe.com.
  • I didn't find what I was looking for, can I contact you?
  • Contact us with any question...