Robot that carries out learning control in applications requiring constant speeds, and control method thereof

A robot, comprising:

• a robot mechanism unit provided with a sensor for detecting a position of a control target;
• and
• a control device having a learning control unit and configured to control an operation of the robot mechanism unit in accordance with an operation program, and
• means for inputting a priority level for at least one of an allowable condition for processing error, an allowable condition for vibrations, or an allowable condition for a cycle time of learning,
• wherein the learning control unit comprises:
• an operating speed change rate adjusting section configured to calculate an allowable condition for speed variations during a processing operation based on the allowable condition for processing error, and adjust an operating speed change rate of the robot mechanism unit based on the calculated allowable condition for speed variations within a range of the allowable condition for vibrations;
• and
• a correction amount calculating section configured to calculate a correction amount to suppress the vibrations in the adjusted operating speed change rate,
• wherein the learning control unit, in a case where any allowable condition is not met, is configured to continue the learning while relaxing the allowable conditions based on the priority level.

A control method of a robot, the robot comprising:

• a robot mechanism unit provided with a sensor for detecting a position of a control target and a control device configured to control an operation of the robot mechanism unit in accordance with an operation program taught to carry out the operation at a constant speed, the control method comprising:
• causing the robot mechanism unit to operate according to an operation command pertaining to a target trajectory or a target position of the control target;
• storing a maximum speed and a minimum speed caused by limitations of the robot mechanism unit during a processing operation to be carried out in accordance with the operation program;
• calculating an allowable condition for speed variations corresponding to a ratio between the maximum speed and the minimum speed;
• setting an operating speed change rate to increase or reduce an operating speed of the robot mechanism unit, based on the calculated allowable condition for speed variations and the stored maximum speed and minimum speed;
• calculating an amount of difference between the position of the control target detected based on the sensor and the target position;
• adjusting the operating speed change rate within a range not exceeding a maximum value of the operating speed change rate and within a range of an allowable condition for vibrations occurring in the control target;
• and
• carrying out learning of calculating a new correction amount based on the amount of difference and a correction amount previously calculated to suppress the vibrations in the operating speed change rate.