Numerical controller having corner path generation function in consideration of post-interpolation acceleration/deceleration

A numerical controller which controls a machine tool comprising a plurality of control axes so as to compensate an inward turning error by inserting a curved movement path into a corner section between two consecutive blocks in a machining program comprising a plurality of blocks, the numerical controller comprising:

• non-transitory computer readable memory;
• one or more hardware processors coupled to the non-transitory memory and configured to read instructions from the non-transitory memory to cause the numerical controller to perform operations comprising:
• determining that an actual inward turning amount, Sa, is greater than the allowable inward turning amount, ls, at the corner section, wherein Sa is the sum of the maximum allowable inward turning of a curve, l, and an inward turning amount, S, for circular arc interpolation, wherein Sa being greater than ls indicates that the machine tool exceeds its tolerance;
• inserting the curved movement path into the corner section with a new allowable inward turning amount, ls′, wherein ls′ is computed as the difference between ls and S, and ls′ is greater than or equal to an inward turning amount of the curve, l′, wherein a new actual inward turning amount, Sa′, is equal to the sum of l′ and an inward turning amount due to post-interpolation acceleration/deceleration, S′, and Sa′ is less than the ls at the corner section;
• and
• controlling the machine tool according to the inserted curved movement path.