A Novel Automated Approach for Geometric Reconstruction and Flexible Remanufacturing of Spur Gears Using Point Cloud Mapping Analysis

Abstract

In the modern manufacturing era, the atomization of industrial equipment and maintenance activities is a core of industrial evaluation. The growing geometric complexity of products in industrial sectors requires maintaining the reliability and durability of production considering the zero-defect manufacturing concept. In this regard, monitoring product features both during manufacturing and operational processes along with periodical tests and analysis of parts are required. In this study, an automated remanufacturing process of industrial parts via surface point clouds is developed as a step towards smart maintenance. In fact, this flexible remanufacturing method reduces spare part supplying delays. First, a 3D laser scanner is used to provide a numerical 3D representation of industrial spur gear surfaces as a triangulated mesh. Then, using automated geometry recognition on this mesh, a computer-aided design (CAD) model of the scanned part is reconstructed. The geometry of this CAD model is then modified to reinforce the worn gear and to respect gear profile standards. By comparing CAD and scan data, freeform surfaces of this reconstructed CAD model are finally verified and adjusted to meet a set of assembly conditions. This leads to the reconstruction of an optimized CAD model, which is then used to build a gear mold. This mold is fabricated using a MultiJet Printing™ (MJP) plastic additive manufacturing machine. Analyzing mechanical properties of the worn gear, polyurethane as the fabrication material is gravity-casted in a mold and cured. Based on the proposed method, a worn and damaged spur gear of heavy-duty equipment in the mining industry is remanufactured. The equipment is thus repaired by replacing the worn gear with a remanufactured spare gear, which fulfills its nominal performance. It is worth underlying that the proposed approach allows reducing downtime of this equipment from, as estimated, six months to three weeks.