ROBUST METHOD FOR STRAIGHTNESS EVALUATION: COMBINED LS AND PSO METHODS
IHAB HAMDY NAEIM *
Faculty of Science, Taibah University, Preparatory Deanery, Yanbu, Saudi Arabia. and Precision Engineering Division, National Institute of Standards (NIS), Giza 12211, Egypt.
*Author to whom correspondence should be addressed.
Uncertainty and metrological traceability are always an aim of metrology scientists to verify the true value of measuring process. This work reports on a reliable and robust method for estimating the CMM straightness by systematically employing a combination of the least-square LS and particle swarm-optimization PSO methods. Repetitive acquisition of the data points was performed along a straight line in a flat slab using advanced CMM measurement system. The least-square method gave rise to smaller straightness 7.22 μm with larger error ±0.20 μm as compared with the particle-swarm-optimization PSO method 9.08±0.13 μm. The combined average 8.15±0.11 μm of the results obtained by the two methods thus pertains to the better straightness from the LS method as well as the better accuracy from the PSO method.
Keywords: Straightness metrology combined LS, PSO computational methods