Virtual reality vs. lecture-based learning in additive manufacturing: A quasi-experimental analysis using FABRICATE

As additive manufacturing (AM) continues to reshape industrial production, there is a growing need for effective and inclusive educational strategies that prepare learners with both conceptual knowledge and practical skills. This study presents a quasi-experimental evaluation comparing traditional lecture-based instruction with a bilingual, theoretically grounded virtual reality (VR) training platform—FABRICATE (Fully Accessible Bilingual VR Interface for AM Training and Education). FABRICATE simulates realistic AM processes using interactive case studies, guided training modules, and performance-based assessments in a fully immersive environment. Undergraduate engineering students were assigned to either the VR or lecture group, receiving equivalent content tailored to powder bed fusion (PBF) operations. Pre- and post-learning assessments measured their performance on declarative knowledge and procedural skills. Causal inference–oriented methods, including t-tests, regression analyses, and unsupervised clustering, were used to examine associations between instructional modality and learning outcomes. Results show that VR-based instruction significantly enhances procedural learning and yields more consistent performance, while both modalities achieve comparable gains in conceptual understanding. A strong inverse correlation between prior knowledge and learning gain suggests a ceiling effect. Subgroup analyses suggest that prior VR experience and its unequal distribution across demographic groups may influence engagement and performance in immersive learning environments; however, these findings are exploratory and warrant cautious interpretation. In this study, because participants were assigned by course enrollment rather than random assignment, findings should be interpreted as evidence consistent with instructional modality effects rather than definitive causal estimates. These findings contribute to a deeper understanding of how immersive technologies can be leveraged to support more effective and equitable AM education and workforce training.