Accurate alignment of laminate materials using sensor-based robot techniques

Assembly accuracies of 0.05-0.1 mm, needed for electronic product manufacture, are attainable with current automated manufacturing equipment. Aggressive electronic system designs will require manufacturing accuracies in the range of 0.005-0.01 mm. A system and strategy is described here to fabricate circuit boards requiring alignment accuracies of 7.5 /spl mu/m using existing automation equipment with enhancements and typical manufacturing line fixtures. The system, configured as a pilot workcell, consisted of an IBM 7576 coarse positioning robot, a fine positioning manipulator, an optical sensing system and a unique bracing method to reduce environmental disturbances. The strategy was to use a coarse/fine placement technique with sensing to align, stack and bond individual test laminates with patterns of 100 /spl mu/m holes. The results showed that pairs of holes were consistently aligned to 2-5 /spl mu/m which surpasses the 7.5 /spl mu/m manufacturing requirement.< >