Coordinate measurement machine with individual frame pillar drives - has auxiliary controller arrangement ensuring minimal difference in pillar positions

摘要

The coordinate measurement machine has a frame with two pillars with individual y-direction drives (6, 7). The drive (6) in the first pillar has a main controller (16) whose inputs are the desired displacement and the actual displacement for this pillar. The second pillar's drive (7) has an auxiliary, synchronous controller (17) whose inputs are the desired displacements for the two pillars. It forms a control parameter from these inputs which is added to that of the main controller and used as the corrected control signal for the second drive. ADVANTAGE - Ensures that difference in positions of pillars in actual or measurement positions is less than measurement uncertainty.