Abstract
In this study, an on-line forecasting compensatory control (FCC) strategy is successfully employed to improve the workpiece accuracy in taper machining by compensating the relative two-dimensional motion errors between the workpiece and the cutting tool. The indirect measurement set-up is developed to determine the motion errors, in both radial and longitudinal directions, of the spindle which positions the workpiece via a master taper. Also, the straightness motion errors of the x-y slide are determined to give the actual tool positions. The reference datum in these measurements, i.e. the master form error and the slide profile, can be determined under on-machine conditions and highly accurate precalibrated references are not required. Based on the autoregressive moving average (ARMA) technique, the two-dimensional motion errors are modelled and their future values forecasted and compensated by means of a piezoelectric actuator. The adequate model order and parameters are found by performing off-line simulations. The effectiveness of the FCC strategy is also evaluated by comparing the roundness results with and without compensation. Experimental cutting with FCC reveals that a maximum improvement of 68 per cent and an average improvement of 41 per cent can be achieved for workpiece roundness in this taper machining process.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have