Rapid and high-precision measurement of global surface sphericity error using spectral confocal sensors

Abstract

To address limited data coverage and inaccurate assessment in sphericity measurement due to limited field of view and fixturing constraints, this paper proposes a rapid and high-precision full-sphere sphericity error measurement method integrating spectral confocal measurement with dual‑spindle coordinated motion. A system with a dual-spindle structure and three-axis displacement platform is developed. By adjusting the relative positions of the spectral confocal sensor, workpiece, rotary stage, and spindle, the system ensures proper alignment of the centers axes, enabling continuous scanning and dense point cloud acquisition covering the entire spherical surface. Experimental tests on standard and rough spheres show measurement errors under 3 μm compared to a coordinate measuring machine, while verification via the national standard evaluation method confirms superior repeatability, stability, and data completeness, allowing the generation of a complete sphericity distribution map. This study provides an efficient non-contact solution for sphericity inspection, with significant value for online quality control and process optimization of precision spherical components.