PC-DMIS offers two procedures that allow you to set the probe depth on a sphere. Depending where the probe is located in relation to the centerline of the drawing determines where the hit is taken on the sphere. If the probe is below the centerline, PC-DMIS takes the hit on the bottom of the sphere. To take a hit on the top of the sphere, the probe depth must be set above the centerline.
For additional information on the following procedures, see "Measuring Features Offline".
Three-Dimensional Procedure
To set the precise depth on a three-dimensional spherical surface:
Move the animated probe to the desired circle.
Hold down the right mouse button.
Release the mouse button. The precise depth is set on the sphere.
PC-DMIS positions the probe on the side of the feature where the mouse button was first held. This determines the type of feature that is measured. If the probe snaps to the outside of a circular CAD element, the hits are placed outside the circle. If the probe snaps to the inside of the same element, the hits are placed inside the circle. The circle’s three-dimensional origin must be the same location as the sphere’s center.
Once the precise depth has been set, all the points that are generated snap on to the spherical surface.
Two-Dimensional Procedure
When you use a two-dimensional drawing, PC-DMIS requires at least two views of the sphere. The sphere should be visible as a circle (or arc) in both views.
Set the precise depth for two of the axes using one of the views. PC-DMIS displays this message: "Precise Depth Set on". See "Setting Probe Depth on a Feature" for setting the precise depth.
Use the second view to set the precise depth for the third axis. PC-DMIS displays this message: "Precise Depth Set on Sphere". This procedure finds the true three-dimensional center point of the sphere.
Once you have set the precise depth, all the points that are generated snap on to the spherical surface.