Design assist apparatus, design assist method, and design assist program for a mechanical device driven by a feedback controlled electric motor

A design assist method for assisting design of a mechanical device driven by a feedback controlled electric motor, comprising the steps of:

• setting a plurality of parameters of a mathematical model of a mechanical component forming the mechanical device that are adjustable,
• computing a pole of a transfer function of the mechanical device associated with one or more vibration modes of the mechanical device according to the parameters, and
• creating and displaying a stability determination diagram including an isoline of a real part of the pole of the transfer function with respect to the parameters, the isoline defining a stable region where a value of the real part is negative and an unstable region where a value of the real part is positive, the stability determination diagram including one or more symbols respectively corresponding to one or more candidates for the mechanical component, each symbol indicating parameters of a corresponding candidate.

A computer-readable storage medium storing a design assist program for executing a process for assisting design of a mechanical device driven by a feedback controlled electric motor, the program causing a computer to execute the procedures of:

• setting a plurality of parameters of a mathematical model of a mechanical component forming the mechanical device that are adjustable,
• computing a pole of a transfer function of the mechanical device associated with one or more vibration modes of the mechanical device according to the parameters, and
• creating and displaying a stability determination diagram including an isoline of a real part of the pole of the transfer function with respect to the parameters, the isoline defining a stable region where a value of the real part is negative and an unstable region where a value of the real part is positive, the stability determination diagram including one or more symbols respectively corresponding to one or more candidates for the mechanical component, each symbol indicating parameters of a corresponding candidate.