Calibrating force sensor
Keywords Sensors, Calibration, Robots
Applicant: Fanuc Ltd (JP)Patent number: EP0937974Publication date: 25 August 1999Title: Method for calibrating sensor mounting on robot, and robot
A method for executing calibration without having to dismount a force sensor from a robot, and an apparatus for executing this method are provided. When a robot mounted with a calibrated force sensor begins to be operated, any tool whose position of the centre of gravity and weight are immune from change is fitted, and a command for acquiring reference data is given to execute operational programs. Reference data of matrices consisting of differences between strain gauge outputs of the force sensor in any predetermined posture and strain gauge outputs in other predetermined postures differing both from that posture and from one another are calculated and stored. When the measuring accuracy of the force sensor drops, the tool used when the reference data were acquired is mounted on the robot, and the same procedures are executed, and the data corresponding to the reference data are calculated. From the data and the reference data is calculated a parameter for updating the calibration matrices.
Jack Hollingum
