Robot and collision detection method therefor
AssigneeFanuc Corporation
InventorShizuo Harada
Life of this patent
Estimating the term…
Abstract
Provided is a robot including: a robot body that is provided with at least one arm; a gas spring that functions as a balancer for the arm of the robot body; an internal-pressure detecting unit that detects a cylinder internal pressure of the gas spring; and a control device that controls the robot body. The control device calculates, as an estimated disturbance value, the difference between a torque command value for a servomotor that drives the arm and a torque of the servomotor that is required to actually operate the arm, determines that the robot body has had a collision when the estimated disturbance value exceeds a predetermined threshold, and corrects the estimated disturbance value or the threshold on the basis of the cylinder internal pressure detected by the internal-pressure detecting unit.
Claims5
A robot comprising:
- a robot body that is provided with at least one arm;
- a gas spring that functions as a balancer for the arm of the robot body;
- a pressure sensor that detects a cylinder internal pressure of the gas spring;
- and
- a controller that stores a reference internal pressure for the cylinder internal pressure
- wherein every time a predetermined time for detecting the cylinder internal pressure of the gas spring arrives, the controller is configured to:
- calculate, as an estimated disturbance value, a difference between a torque command value for a servomotor that drives the arm and a torque of the servomotor that is required to actually operate the arm and calculate a pressure difference between the cylinder internal pressure detected by the pressure sensor and the stored reference internal pressure;
- correct the calculated estimated disturbance value or a predetermined threshold on the basis of the calculated pressure difference;
- and
- detect a collision of the robot body by comparing the corrected estimated disturbance value with the predetermined threshold or comparing the calculated estimated disturbance value with the corrected predetermined threshold.
A robot collision detection method for a robot including a robot body that is provided with at least one arm and a gas spring that functions as a balancer for the arm of the robot body, the method comprising:
- detecting, every time a predetermined time for detecting a cylinder internal pressure of the gas spring arrives, the cylinder internal pressure of the gas spring and
- calculating, as an estimated disturbance value, a difference between a torque command value for a servomotor that drives the arm and a torque of the servomotor that is required to actually operate the arm;
- calculating a pressure difference between the detected cylinder internal pressure and a reference internal pressure for the cylinder internal pressure;
- correcting the calculated estimated disturbance value or a predeterminde threshold on the basis of the calculated pressure difference;
- and
- detecting a collision of the robot body by comparing the corrected estimated disturbance value with the predetermined threshold or comparing the calculated estimated disturbance value with the corrected predetermined threshold.
Dependencies are inferred from the claim text.