A New Optimal Method of Tool Path Generation for Slow Tool Servo Turning of Complex Surface

Abstract

In order to improve the surface machining quality of slow tool servo (STS) turning in complex surfaces, the optimal method of tool path generation (TPG) was studied. Taking into consideration the problem of large discrete errors and interpolation errors in TPG, equal height discretization method and interpolation algorithm for non-uniform nodes were proposd and the acceleration continuous condition was introduced. Simulation results showed that equal height discretization method could reduce the discrete error by more than 70%. The interpolation errors could be reduced to two orders of magnitude by transforming segment cubic Hermite interpolation into segment cubic spline interpolation. Finally, the processing experiments were performed. The results showed that the form error PV value for the workpiece of the toric surface obtained by equal height discretization method and non-uniformity processing and segment cubic spline interpolation reached 0.002mm. The PV value of the sinusoidal array surface was about 0.009mm, and its surface roughness value was 0.064μm. The results proved this method can effectively reduce the discrete errors and interpolation errors, as well as improve the surface machining quality.

Development of a Surface Roughness Prediction Model for Slow Tool Servo Turning Machining

“…In slow tool servo turning the point where the tool edge is at a tangent to the machined surface is called the cutting contact point (CCP). Since the CCP can be any point on the tool edge during cutting, it is necessary to specify a fixed point on the tool to determine the position of the tool in the cutting process, which is called the cutting location point (CLP) [13]. The tool trajectory in slow tool servo turning machining should be consistent with the CLPs.…”