DUTY-BASED MINIMUM-TIME CONTROL METHOD FOR ROBOT

摘要

A duty-based minimum-time control method for a robot, which takes the operation duty into consideration in order to prevent overheat of servomotors for driving shafts of the robot. When a regenerative operation of the robot is started, monitoring of each shaft motor current is started (S1). Accelerations Aac and Adc are determined in accordance with the minimum-time control method (S3 to S6). Aac' and Adc' are obtained by multiplying the accelerations Aac and Adc so determined by an adjustment parameter k (initial value 1) (S7). Time constants τac and τdc of the acceleration/deceleration operation are determined on the basis of Aac' and Adc' (S8). When one operation cycle of the robot is completed, the root mean square of the motor current monitored is calculated and is compared with an allowable value (S12). When the root mean square exceeds the allowable value, the value of the parameter k is reduced and adjusted to αk (S13).