Research on a weighting alignment method for investment casting turbine blade shape inspection

Turbine blade is a critical component of the aero engine, needs carefully inspection at its production stage. In order to align the measurement data of the investment casting turbine blade and its CAD model to unify the coordinate system for its geometric shape inspection, an accurate alignment method based on the ICP (Iterative Closest Point) using weighting strategy is presented. The weight of each alignment control point is assigned according to the blade thickness value at the point location. The optical photography measurement data of real turbine blade is adopted as testing data for the alignment method. Experimental results show that the discussed method can enhance the alignment accuracy effectively.