Which term describes a 3D printing technique that places melted layers of material on a bed to build up a 3D model?

• A. Fused deposition modelling (FDM)
• B. Graphical models
• C. Haptic technology
• D. Motion capture

Answer: (A)

This describes fused deposition modelling, a 3D printing technique where melted material is deposited in layers on a build bed to create a model. A thermoplastic filament is fed into a heated nozzle, melts, and is extruded in thin lines along programmed paths. Each new layer is laid on top of the previous one, and as the material cools it bonds to the layer beneath, building the object from the bottom up. Materials commonly used include PLA, ABS, and PETG. The other terms refer to digital representations (graphical models), touch feedback devices (haptic technology), or recording movement (motion capture), not a process that builds a physical object by layering melted material.