Rapid generation method of polishing trajectory based on removal model constraints

Precision polishing, as the final machining operation for aero-engine blades, directly determines the profile accuracy and surface integrity of the airfoil. However, traditional polishing processes are troubled by error accumulation caused by non-uniform material removal and inefficient trajectory planning. Manual polishing, on the other hand, incurs high costs and results in inconsistent quality. To solve these problems, this paper proposes a rapid polishing trajectory generation method constrained by a material-removal model. The pre-pressing amount at each cutter location is derived based on the material-removal model, establishing quantitative relationships between material-removal depth, curvature radius, and pre-pressing amount. An implicit relationship between pass width and surface curvature is formulated. Moreover, a rapid search strategy for the narrowest line-width point is developed by integrating principal curvature prediction and regional constraints, enabling efficient localization of critical tool positions. Experimental verification on TC4 titanium-alloy blades shows that the profile accuracy is significantly improved. The profile error is reduced from [+ 0.075335, + 0.172321 mm] to [+ 0.04708 mm, + 0.07977 mm], and the profile deviation is improved from + 0.069272 mm to + 0.02899 mm. This method strikes a balance between machining efficiency and polishing accuracy, offering an effective way to polish complex-curved blades.