The basic technique utilizes both tangential and normal data points that are based on the probe coordinate system. The system is located at the #5 and #6 encoder interface.
The starting position of the arm is the same as with only a straight probe. The arm is folded over horizontally to the right of the operator. The #6 encoder is vertically above the #5 encoder. Maintain this orientation while taking 5 data points from the 12 o’clock position, moving in a clockwise direction, down to the 6 o’clock position.
Rotate encoders #5 and #6, encoder #6 will now be located vertically above encoder #5. Digitize 5 points clockwise from the six o’clock position to the 12 o’clock position. Maintain a constant probe orientation throughout this process.
Reposition the #5 and #6 encoder so that the #6 encoder is vertically above #5. The probe should be held normal to the surface of the 1” sphere. Digitize two points on the northern hemisphere of the 1” sphere. Locate the first point directly at the north pole and the second point just forward of the first point (toward the operator).
Reposition encoders #5 and #6, placing encoder #6 vertically above #5. Digitize two points on the bottom hemisphere of the 1” sphere. Digitize the first point at the southern pole and the second point just forward of the first.
Starting at the 3 o’clock position with the #5 encoder vertically above the #6 encoder, digitize 4 points along the equator. Keep the probe tangent to the 1” sphere. Point #4 is located at the front of the sphere. Rotate encoder #6 180 degrees and digitize three points along the equator starting left of point 4 and ending around the 9 o’clock position.
Position arm so that encoder #6 is vertically positioned above #5. Digitize 3 points from the south pole to the north pole. Rotate encoders #5 and #6 180 degrees and repeat this procedure. Digitize the three points from north and ending at the southern most point of the sphere.
Keywords: serial, extension, 90 degree, probe extension