Feed rate scheduling methods include measuring a topography of a grinding wheel of a machine tool, calculating a topography parameter using the topography, and calculating a feed rate scheduling parameter for a toolpath of the grinding wheel based on the topography parameter. The topography may be measured using microscopy. The topography parameter may include a plurality of parameters including a density of crystals at a given depth (C(h)) of the grinding wheel and/or an area fraction of crystals protruding at a given depth (α(h)) of the grinding wheel. The feed rate scheduling parameter may include a grinding wheel feed rate, a grinding wheel spin rate, and/or a grinding wheel cutting depth, among other parameters.

A position controller includes a position detector, a speed command operator, a first adder, a torque command operator, a second adder, a drive unit, a runout amount correcting device, and a third adder. The runout amount correcting device is configured to employ a value related to deviation between a command value and a detection value in physical quantity of a movable part as a reference signal. The runout amount correcting device is configured to calculate a position correction amount from rotation angle information of the main spindle and the reference signal. The runout amount correcting device is configured to estimate a runout amount of a cutting edge of the tool from the reference signal. The runout amount correcting device is configured to calculate the position correction amount such that influences of the respective cutting edges appearing in the reference signal are leveled.