Forward kinematic calibration and gravity compensation for parallel-mechanism-based machine tools

Abstract

This paper describes a newly developed forward kinematic calibration method for parallel mechanisms, which identifies the kinematic parameters using the positioning data measured by a Double Ball Bar (DBB) system. This method enables precise calibration with easy measurements, which improves the static accuracy reduced by kinematic parameter errors. This paper also describes a new gravity compensation method, in which the kinematic parameters are updated gradually according to the travelling plate position. This provides real-time motion control with compensation. These methods are applied to the parallel-mechanism-based milling machine, named HexaM, and their validity is verified by simulation and experiment.

Keywords

parallel mechanism kinematic calibration forward kinematics gravity compensation elastic deformation HexaM Double Ball Bar system

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References

Innocenti

Algorithms for kinematic calibration of fully-parallel manipulators In Computational Kinematics (Eds Merlet

J. P.

Ravani

), 1995, pp. 241–250 (Kluwer Academic Publishers).

Kugiumtzis

Lillekjendlie

Estimation model for kinematic calibration of manipulators with a parallel structure

J. Robotic Systems, 1994, 11 (5), 399–410.

Zhuang

Roth

Z. S.

Method for kinematic calibration of Stewart platforms

J. Robotic Systems, 1993, 10 (3), 391–405.

Geng

Z. J.

Haynes

L. S.

An effective kinematic calibration method for Stewart platforms In Proc. 5th International Symposium on Robotics and Manufacturing, 1994, pp. 87–92.

Zhuang

Masory

Yan

Kinematic calibration of a Stewart platform using pose measurements obtained by a single theodolite In Proc. International Conference on Intelligent Robots and Systems, 1995, Part 2, pp. 329–334.

Tamaki

Uno

Mita

Sugimoto

Sakaue

Onari

A restructurable assembly centre employing mobile DD-robots In Proc. 24th International Symposium on Industrial Robots, 1993, pp. 119–126.

Sakakibara

An automatic calibration method for improving absolute positioning accuracy of a robot arm In Proc. 24th International Symposium on Industrial Robots, 1993, pp. 905–910.

Masory

Wang

Zhuang

On the accuracy of Stewart platform—Part II kinematic calibration and compensation In Proc. 1993 IEEE International Conference on Robotics and Automation, Vol. 2, 1993, pp. 725–731.

Svinin

M. M.

Uchiyama

Contribution to inverse kinematics of flexible robot arms

JSME Int. J., 1994, Series C, 37 (4), 755–764.

10.

Judd

R. P.

Knasinski

A. B.

A technique to calibrate industrial robots with experimental verification In Proc. 1987 International Conference on Robotics and Automation, 1987, pp. 351–357.

11.

Chen

Chao

L. M.

Positioning error analysis for robot manipulators with all rotary joints

IEEE J. Robotics Automation, 1987, RA-3 (6), 539–545.

12.

Soons

J. A.

Measuring the geometric errors of a hexapod machine tool. In Proc. 4th Lamdamap Conference, 1999.

13.

Lintott

A. B.

Dunlop

G. R.

Geometric modelling of general parallel mechanisms for calibration purposes In Advances in robot kinematics: analysis and control (Eds Lenarcic

Husty

M. L.

), 1998, pp. 175–184 (Kluwer Academic Publishers).

14.

Week

Staimer

Accuracy issues of parallel kinematic machine tools—compensation and calibration. In Proc. 2000 Parallel Kinematic Machines International Conference, 2000, pp. 35–41.

15.

Pierrot

Shibukawa

From Hexa to HexaM In Proc. 1st European-American Forum on Parallel Kinematic Machines, 1998.

16.

Denavit

Hertenberg

R. S.

A kinematic notation for lower-pair mechanism based on matrices

ASME J. Applied Mechanics, 1955, 22, 215–221.