Industrial Robot Calibration Creates a Metrology Robot

Robot calibration is becoming more popular as it can remarkably improve the accuracy of industrial robots. Industrial robots are highly repeatable but not very accurate. However, through a robot calibration process the accuracy of a robot arm can be improved to the point where it is close to its repeatability, usually under the 0.100 mm mark. This is becoming very attractive to manufacturing enterprises as articulated arm robots are very affordable compared with Coordinate Measuring Machines and can be integrated with both optical and laser scanning sensors and utilised for production metrology applications.

The work accomplished by Neoset Designs Inc demonstrates the capabilities and results that can be obtained using RoboDK’s offline programming and robot calibration combined. Neoset Designs manufactures unique pieces of art for well renowned artists and designers such as Barry X Ball and Elie Tahari.

The accuracy of a KUKA KR 210 robot and a KUKA KR 120 R2500 was improved to better than 0.200 mm. The calibration was accomplished by taking less than 100 measurements using the Creaform’s Portable CMM. Compared to other adaptive compensation methods, robot calibration does not require a permanent measurement system installed on the cell and can reach an accurate position immediately without any measurement iterations. Furthermore, robot calibration can be provided as a product as well as a service in partnership with Creaform.

Robot calibration is the process of identifying the real geometrical parameters in the kinematic structure of an industrial robot, i.e., the relative position and orientation of links and joints in the robot. Robot calibration can be completed in less than 20 minutes. Once you have calibrated your robot with RoboDK you can generate accurate robot programs offline without 3rd party software.

Once the robot is calibrated it is also very easy to compare the accuracy before and after calibration with a ballbar test or an ISO 9283 test (Robot Performance Analysis). Customized path accuracy, speed and acceleration tests can also be run and a detailed report obtained.

Robot calibration procedure (20 minutes)

  1. Base calibration (3 minutes, 9 measurements)
  2. Tool calibration (3 minutes, 9 measurements)
  3. Robot calibration (7 minutes, 60 measurements)
  4. Validation (7 minutes, 60 measurements)

For more information.