Optical 3D shape measurement and wear evaluation method of power head of rotary drilling rig

Abstract Power head of rotary drilling rig is a core work unit, whose wear degree affects work intensity and efficiency. However, there are few reasonable solutions to wear detection of the power head. This paper proposes a method of measuring surface based on optical lattices and applies it to surface reconstruction of power head. In general, we project an optical lattice with a certain regularity onto an object, calculate the three-dimensional shape of surface based on lattice offset on the CCD camera, and then use polynomial fitting to calculate the expression of the surface. The evaluation of the damage degree of the surface data of the power head is converted into a two-dimensional image noise evaluation, and an evaluation model for quantifying the wear degree of the power head is established. In the experiment, we prove the high precision of the optical lattice measurement system in this work. According to the proposed evaluation model, the wear evaluation results are in line with actual ones. Further, this method can be extended to general surface measurement and wear evaluation.