### Sphere

To create a Sphere command:

1. Press the Measure soft key from the Main screen's Navigation Bar.

2. Press the Forward soft key to get to the second page of soft keys.

3. Press the Sphere soft key to display the Measure Sphere screen.

3. Follow the instructions on the screen to insert the command. Pay attention to the graphical description in the upper left section of the screen. It will show you where to position the probe for measurements and changes when multiple steps are required.

Parameters Definition:

- Sphere Center (XYZ Nominal) - Defines the nominal position of the center of the sphere.

- Diameter (Nominal) - Defines the nominal diameter of the sphere.

Properties Definition:

- Number of Points - Provides the total number of points that will be measured.

- Lower level Angle - Defines the lower level angle of the sphere, the equator is 0 degree.

- Upper level Angle - Defines the upper level angle of the sphere, the north pole (top) is 90 degrees.

Note: The difference between the upper level angle and the lower level angle must be at least 20 degrees. This is limited because less than 20 degrees of arc will likely result in inaccurate measurement results.

Motion Parameters Definition:

- Prehit Distance - Defines the distance away from the nominal surface at which the probe will start seeking the surface during measure.

- Search Distance - Defines the search distance when finding and learning a feature.

Optional Settings

- Hit Clearance Plane - Selecting this option causes the probe to move to a clearance plane between each hit of the feature. The edit box to the right will allow the user to enter the distance to the plane. This plane is not the program clearance plane.

- Learn Then Measure - Selecting this option causes the machine to learn the location of the part using default parameters and then immediately re-measure the feature with the properties as set on the screen. This will allow the user to test all the set parameters and should warrant a more accurate and reliable first article inspection.

- Learn Using Values on Screen - This allows the user to enter the nominal values of the feature and have the software measure at that location.

Available Navigation Bar Soft Keys on this Screen:

Learn Process:

1. Position the probe above the sphere center top and press the Read Position soft key .

2. Press the Learning and Creating a Command soft key . NC Gage automatically takes hits in a fashion as depicted below.

Sphere Path: A) jog position 1-4) automatically measured point positions

3. Once the feature has been measured, the measured values are updated. Press the Confirm and Append Current Command to End soft key . The feature command is added to the part program.

The following is the specific feature path and logic built into NC Gage:

Learn Sphere Feature Path

- Read position of probe which should be above the top of the sphere.

- Measure point straight down, using search distance.

- Retract to original read position and move 2* probe radius in the +X direction.

- Measure point straight down, using search distance.

- Retract to original height and move 2* probe radius in direction which is 120 degrees from +X axis.

- Measure point straight down, using search distance.

- Retract to original height and move 2* probe radius in direction which is 240 degrees from +X axis.

- Measure point straight down, using search distance.

- Retract to original height.

Execute Sphere Feature Path

- Number of levels and points for each level are determined based on the number of points to measure which is defined on the form.

- If current position is lower than the clearance plane height then move up to clearance plane.

- Move to position above the first prehit point.

- Drop down to lowest level and measure that level, if needed evasive moves are added between each point in a level to avoid collisions.

- Measure the rest of the level(s) using alternating directions.

- Measure point on top of sphere (if upper level angle is 90).

- Move to clearance plane height.