COORDINATE SYSTEMS

Part Coordinate System:

A measured dimension is erroneous or meaningless if it is not properly tied to a valid Part Coordinate System (PCS). Geomet therefore historically has and still does put great emphasis on the correct and efficient establishment of a PCS. This is one of Geomet’s great strengths when measuring prismatic parts.

Highly flexible PCS formation tools allow easy establishment of datum frames for parts in any position on the machine. Basic PCS set up commands consist of ORIENT, ALIGN and ORIGIN for the construction of Primary, Secondary and Tertiary datums. A handy PCS Setup Guide serves as a visual reminder of any missing steps in the construction of a PCS. Multiple PCSs can be created during an inspection operation and the operator is free to move in and out of any PCS at any time. As PCSs are created, they are automatically saved. A 3D icon in the graphics area indicates the location and orientation of the currently active PCS as a visual reference.

PCSs can be translated in any or all axes to create new PCSs. They can also be rotated around any axis. Features measured in one PCS will automatically be projected correctly into a new PCS if recalled in one. The elements of PCSs (for example, an origin, a datum axis or a datum plane) can be extracted for use in other constructions or PCSs. Up to 500 PCSs can be created and recalled.

Pre-established and stored Fixture Coordinate Systems (FCS) are handy, timesaving tools in the repetitive inspection of production parts that are fixtured. FCS eliminates the manual PCS formation procedure to locate the part or parts for each run. Unlimited FCSs enable you to check many or different parts in a run.

Geomet has fourth axis capability, referred to as a Wobble Coordinate System (WCS), permitting the use of Rotary Tables.  The software compensates for table runout.  A typical application for a WCS is in Helmel’s automatic shaft and crankshaft CMMs with Horizontal Rotary Axis.