Gap detection device and gap detection method for robot joint

A gap detection method for a robot, the robot comprising:

• a drive link configured to be driven by a motor;
• a plurality of passive links configured to be driven by a motion of the drive link;
• and
• a plurality of pairs respectively connected to the plurality of passive links,
• wherein the gap detection method is to detect a first gap amount between pairing elements of a pair connected to the passive link, and the gap detection method comprises the steps of:
• measuring a drive torque or a current value of the motor when the robot is actually moved along an arbitrary motion trajectory;
• setting an arbitrary second gap amount between pairing elements of the plurality of pairs, executing a simulation in which the robot is moved along the same motion trajectory as the arbitrary motion trajectory, and estimating the drive torque or the current value of the motor;
• calculating a first feature amount representing a variation in a value relating to the measured drive torque or the measured current value and a second feature amount representing a variation in a value relating to the estimated drive torque or the estimated current value;
• and
• calculating an index relating to the first gap amount based on the first feature amount, the second feature amount and the second gap amount.

A gap detection device for a robot, the robot comprising:

• a first link configured to be driven by a motor;
• a second link configured to the first link;
• and
• one or more pair connected to the second link,
• wherein the gap detection device is configured to detect a first gap amount between pairing elements of a pair connected to the second link, and the gap detection device comprises:
• a measurement unit configured to measure a first output value of the motor when the robot is actually moved along an arbitrary motion trajectory;
• a simulation unit configured to set an arbitrary second gap amount between pairing elements of the pair, execute a simulation in which the robot is moved along the motion trajectory, and estimate a second output value of the motor;
• and
• a gap calculation unit configured to calculate the first gap amount based on a change in the first output value, a change in the second output value and the second gap amount.