The disclosure provides a method for manufacturing an ophthalmic device, comprising machining to provide a predetermined surface on a part and which corresponds to an initial ophthalmic surface, the machining comprising: selecting (130) a machining tool having a cutting edge; selecting (140) the initial ophthalmic surface of the ophthalmic device intended to be manufactured; providing (150) a determined kinematics of the machining tool which is function of the initial ophthalmic surface and of a wear parameter of the cutting edge; machining (160) the predetermined surface according to the determined kinematics of the machining tool; wherein the wear parameter is function of at least a distance travelled by the cutting edge for machining the predetermined surface and/or a friction time between the cutting edge and the part which is machined.

The disclosure provides a method for manufacturing an ophthalmic device, comprising machining to provide a predetermined surface on a part and which corresponds to an initial ophthalmic surface, the machining comprising: selecting (130) a machining tool having a cutting edge; selecting (140) the initial ophthalmic surface of the ophthalmic device intended to be manufactured; providing (150) a determined kinematics of the machining tool which is function of the initial ophthalmic surface and of a wear parameter of the cutting edge; machining (160) the predetermined surface according to the determined kinematics of the machining tool; wherein the wear parameter is function of at least a distance travelled by the cutting edge for machining the predetermined surface and/or a friction time between the cutting edge and the part which is machined.

An abrasive article evaluation system is presented that includes a detector that detects a nonvisual abrasive wear cue and an efficiency indication generator that, based on the abrasive wear cue, generates an indication of wear for the abrasive article. The system also includes a command generator that generates a command based in the generated indication of wear.

A numerical control device according to one aspect of the present disclosure capable of easily setting a tip point control is provided with: an edge shape information storage unit; a center position calculation unit that calculates a center position of rotation of a multi-edge tool having machining edges; an edge switching determination unit that determines whether or not edge switching is to be performed; a calculation method changing unit that takes the edge shape information into account and changes, in association with the edge switching, a method for calculating the center position by the center position calculation unit; a tip position back calculation unit that, on the basis of the calculation method changed by the calculation method changing unit, back-calculates a tip position after the edge switching from the center position immediately before the edge switching; and a change amount calculation unit that calculates, on the basis of a tip position and a shaft angle before the edge switching and the tip position and a shaft angle after the edge switching that have been calculated by the tip position back calculation unit, a required change amount of the center position, and calculates a driving amount of a driving shaft for moving a tool rotation axis by the calculated change amount.

A numerical control device according to one aspect of the present disclosure capable of easily setting a tip point control is provided with: an edge shape information storage unit; a center position calculation unit that calculates a center position of rotation of a multi-edge tool having machining edges; an edge switching determination unit that determines whether or not edge switching is to be performed; a calculation method changing unit that takes the edge shape information into account and changes, in association with the edge switching, a method for calculating the center position by the center position calculation unit; a tip position back calculation unit that, on the basis of the calculation method changed by the calculation method changing unit, back-calculates a tip position after the edge switching from the center position immediately before the edge switching; and a change amount calculation unit that calculates, on the basis of a tip position and a shaft angle before the edge switching and the tip position and a shaft angle after the edge switching that have been calculated by the tip position back calculation unit, a required change amount of the center position, and calculates a driving amount of a driving shaft for moving a tool rotation axis by the calculated change amount.