**Figure 6.**

*Geometry of the grain locus in curve generation.*

small segments. The rotational radius Rp in each segment is determined with the actual (or theoretical) shape of the cutting edge. By calculating the engaging depth at each time step with calculated stone posture (inclination and tilting angles), the time series of the engaging depth can be calculated in any stone locus and attitude.

#### *Tribology of Machine Elements - Fundamentals and Applications*

**Figure 7.** *Schematics of the successive grain engaging by the spherical stone.*
