Abstract
In this paper, a microcomputer aided system for the calibration of the flatness of engineering surfaces is proposed. Rectangular grid-type measurement procedures with closing error technique are offered for angular assessment on the surfaces using electronic precision level. A new technique called ‘enclose tilt technique’ (ETT) is developed for the analysis of flatness in terms of minimum zone, and defines the flatness in terms of British and ISO standards. These measurement analysis processes are performed on-line with a microcomputer using an analogue/digital interface, amplifier with low-pass filter, triggering technique, etc., and appropriate high-level and low-level programming language. A practical flatness calibration of a granite table has been performed for application, and the results are shown with up to 0.1 μm uncertainty. The effect of the weight of the precision level, and the rigidity test of the granite table have also been assessed.