AVOIDING HEAVY COMPUTATIONS IN INVERSE CALIBRATION PROCEDURE FOR 7 DOF ROBOT MANIPULATOR
Procedure for determining commanded coordinates in machine space if desired coordinates are given is inverse calibration. A large amount of data is considered after measurement procedure and it is essential to locate desired point in the real space which is skewed due to measured geometric errors. The machine workspace is divided to cells using measurement points. It is depicted the importance of finding the proper cell in skewed 3D lattice, for calibration of translational axes of ATL machine with large workspace. To calibrate 7 DOF robot manipulator, this algorithm is extended. The problem of finding the proper cell in 7D skewed grid needs heavy computations and takes significant amount of computational time. Few ideas for avoiding these computations are described and the influence on the final precision of the calibration procedure is explored.
Key words: inverse calibration; geometric errors; robot manipulator
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