The gauge head assembly is, in turn, attached to a precision spindle.
The pneumatic measuring circuit, gauge head and precise driving mechanism have been designed.
The gauge head is a closed-loop controlled mechanism comprising a contact force probe that is rigidly attached to a high bandwidth linear translator.
As part of the system level design activities several different architectures of the DPG system, including gauge head and supporting electronic equipment, have been evaluated in detail with the aim to fulfil technical requirements imposed by the integration in ITER.
The gauge head assembly (including force probe and servo drive) has a fundamental mode natural frequency of 330 Hz while scanning the workpiece with a constant contact force typically less than 100 mN.
The objective of the complete tool is to contact the sidewall of the circular feature, translate the probe tip to produce a defined contact force with the workpiece and rotate the gauge head assembly.
Measure inner apertures with the smaller pointed jaws on the back of the dial gauge head.
Use the highest line that is visible to the left of the leading surface of the dial gauge head.
Determine the position of the leading surface of the dial gauge head along the marked scale on the body of the dial gauge.
For example, if the highest line to the left of the leading edge of the dial gauge head is 2 unnumbered lines above the numbered line 3, note that as 3.2 cm (1.260 inches).
