• Ei tuloksia

CONCLUSIONS AND FUTURE WORK

The major contribution of this thesis was developing an algorithm that can calibrate the pivot point automatically. The study for accuracy, precision and robustness also showed that the algorithm could work on its own because there were no failures that required human intervention. However, this does not mean that safety limits on movements should not be applied if the algorithm is used in automatic calibration process. The cali-bration results showed that the algorithm developed in this thesis for pivot point calibra-tion is more accurate than manual calibracalibra-tion. The imaging system is repeatable at least to 10 µm and the algorithm can handle multiple rotation-symmetric tools that have a pivot point. A major result in this thesis was concluding that bottom of the circle works better than the centre of the circle for finding the correct difference between reference pivot point and current pivot point location. However, no single data selection method could be concluded to be the best for this type of application, and thus all data selection meth-ods should remain in the algorithm until more data is gathered.

The absolute accuracy of the algorithm is still unclear, so researching that is necessary.

Optimizing the algorithm for speed by selecting the correct data selection methods for different tools is a logical next step in the development of the algorithm. Also developing a more computationally efficient algorithm for determining the fit value is a topic for future work, especially if it is impractical to optimize performance of the algorithm.

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