Low-cost workflow for 3D digitization and prototyping in mechanical engineering education

Abstract

This study proposes and demonstrates a low-cost, reproducible scan-to-print workflow targeting resource-constrained laboratories. The objective is to integrate 3D digitization and fabrication into project-based courses using widely available tools. A five-phase protocol—image capture, image processing, CAD modeling, manufacturing, and verification—was designed and implemented with smartphone photogrammetry, accessible software, and FFF printing. In course deployment, teams rotate roles and use portfolio-based assessment to document parameters and justify design-for-additive-manufacturing decisions. A didactic knee-orthosis served as the case study. The workflow produced a functional prototype with modest resources: ≈400 photographs, alignment ≈3 h, dense reconstruction 4–5 h, and four segmented prints totaling ≈56 h on standard FFF equipment. Observed operational trade-offs were formalized as decision checkpoints, explicitly supporting engineering reasoning, justification design choices and portafolio based documentation. Results indicate that the smartphone-based pipeline is feasible on mid-range hardware and effectively links measurement, reverse engineering, and fabrication within typical course constraints. This initial work focuses on feasibility and repeatability; educational impact and full-surface metrology will be addressed in future work.