An investigation of residual form error compensation in the ultra-precision machining of aspheric surfaces

In this paper, a compensation method for correcting the residual form error due to tool de-centring in the ultra-precision machining of aspheric surfaces is discussed. The method makes use of the form measurement data from a Form Talysurf system to modify the NC machine code generated by a tool path generator (TPG) software in an ultra-precision single-point diamond turning lathe. The performance of the compensation process was evaluated by a series of cutting tests. The results indicate that the residual form error due to tool de-centring can be significantly reduced with the use of the compensation technique. Better results can be achieved if multi-compensations are used.