Method of and apparatus for ascertaining motion abilities of industrial robot

An industrial robot employing electric motors as drive sources respectively for driving a plurality of functional robot units for movement respectively about a plurality of articulatory axes under the control of a robot control unit, said industrial robot comprising:

• current detecting means for detecting an electric current supplied to each of said electric motors associated with the articulatory axis during motion of an associated functional robot unit about the same articulatory axis;
• first storage means for storing digital values representing the electric currents detected by said current detecting means;
• second storage means for integrating predetermined minute sampling times in a period between a first time and a second time during motion of each functional robot unit, and for storing a sum of said predetermined minute sampling times;
• computing means for calculating a ratio of a root-mean-square value of said electric current supplied to each said electric motor to the rated current of said same electric motor on the basis of said sample currents read from said first storage means at each predetermined minute sampling time and said sum of said predetermined minute sampling times calculated by and stored in said second storage means;
• and
• display means for displaying said root-mean-square values of said electric current supplied to said electric motors and the ratios each of the root-mean-square value of said electric current supplied to each said electric motor to the rated current of said same electric motor calculated by said computing means;
• to thereby ascertain the propriety of motions of said functional robot units about the associated articulatory axes with reference to said rated currents of said electric motors.