Experimental validation of an inductive probe for narrow gap measurement based on numerical modelling

•An inductive probe for narrow weld gaps is studied experimentally.•Results from designed coils closely match the simulated sensitivity to gap position.•The probe measures position, height, width and alignment of gap.•Complete probe results from a representative gap indicate industrial usefulness. Experimental validation of numeric results for an inductive probe shows that narrow gaps between two plates can be measured with accuracy suitable for laser beam welding. A two-coil inductive probe for measurement of the gap was built based on finite element modelling results. The individual coils were calibrated using a complex response method, and results from the physical coils closely match the numerical results regarding distance to gap and lift-off above the plate. The measurement of a realistic gap shows results that can be used in industrial applications for position, plate height and height alignment.