Multi-step error separation technique is one of the most widely used roundness separation technique. It can improve the precision of the roundness measuring instrument. By analyzing the model of multi-step, we can find that it has harmonic suppression and cannot be completely separate the roundness error of the tested parts from the rotation error of the spindle. When we use the M-steps, the km times harmonic in tested parts is lost and is mixed 1:1 with the rotation error of the spindle. In this paper, theoretical provement and simulation analysis of harmonic suppression of multi-step error separation technique are carried out: 1) using a group circular standards to separate the same spindle; and 2) using different steps to separate the same spindle.
With the fast development of the advanced equipment manufacturing toward precision and ultra-precision trend, especially with the continuously improving of the aviation engine’s performance, the problem of high displacement resolution for the large-load two-dimension adjusting and positioning worktable used for the aeroengine assembling become evident. A method was proposed which is based on the invariable restoring force, and the adjusting and positioning physical model was established. The experiment results indicate that under the occasion of a load with 508 kilogram, the worktable has got a displacement resolution of 0.3μm after using the improved method compared to 1.4μm of the traditional method. The improved method could meet the requirements of aviation engine assembling worktable.