Application of fuzzy logic in the selection of part orientation and probe orientation sequencing for prismatic parts

With an increase in complex designs and tighter tolerances, the Coordinate Measuring Machine inspection process has become increasingly more advanced. By inspection planning, design data can be transferred to an inspection system and an entire inspection operation can be carried out with a minimum of time and with reduced uncertainty. The current need is to automate this process completely so that the inspection plan can be generated directly from the design information. Two modules of inspection planning, i.e. selection of part orientation and probe orientation sequencing, have not been dealt with properly. Also, some important factors for the selection of part orientation have been neglected and proper weights have not been given to the probe-orientation sequencing criteria. An attempt was made to overcome these limitations. Both problems have been approached as the ranking of a number of alternatives based on multiple criteria, where each criterion has unequal importance. To get the optimum probe-orientation sequence and stable part orientation, fuzzy logic was applied. Fuzzy sets were obtained and combined using a suitable methodology. To explain and validate the proposed methodology, an example part was taken. As a practical case, an engine block was considered and the results presented.