Align Rotary Axis to Machine Axis

Align Rotary Axis to Machine Axis

Inspection workpiece mounted to 4th axis / rotary table should normally be aligned mechanically to the Machine XYZ axis system, thus features measured from one program run to the next have consistent probing access - i.e. part mounted incorrectly could lead to shank measurements.  There are however cases that part cannot easily be loaded in perfect alignment to Machine axis system - i.e. heavy part, held in collet or other non-repeatable fixture, etc. 

Before Adjustment
After Adjustment
It is possible to add Program steps that automatically Align rotary axis such that part is aligned to CMM.  Program looks something like this:
  1. Move Rotary device to Absolute 0.0 Position
  2. Measure Alignment Datum on Part - i.e. front edge of part or other feature used for Alignment
  3. Report Angle of feature compared to Machine X Axis
  4. Save this angle to VB Script Variable using GetReportInfo() command
  5. Rotate Rotary device according to VB Script Variable from above
  6. Perform Relative Rotation for all subsequent Rotary motion in Program

VB Script looks something like this:
  1. MyAng = GetReportInfo("ANGL BT LINE1 and X AXIS", "3D", 2)
  2. MyAng = -1*MyAng

Initial Rotary Table Command looks like this:



See attached sample Program