Digital light processing of a novel oblique-cut spur gear: an integrated framework for additive manufacturing and functional validation

Purpose This study aims to demonstrate how additive manufacturing (AM) overcomes the limitations of traditional gear production, enabling the prototyping and functional validation of a new oblique-cut spur gear that was previously challenging to produce using conventional machining methods. Design/methodology/approach The methodology integrated 3D modeling and virtual motion simulation to design and functionally validate the gear pair. Physical prototypes were fabricated via digital light processing (DLP) using photopolymer resin. The gears underwent inspection for dimensions, hardness and surface roughness, followed by 30 hours of operational testing at 100 rpm and a detailed kinematic-dynamic analysis. Findings Results confirmed a high DLP capability, dimensional accuracy within 0.01 mm, a Shore D hardness of 80 and an average surface roughness of 0.221 µm. The gears mated smoothly under continuous load. Kinematic analysis indicated that the gears behave similarly to conventional spur gears but have cosinusoidal reciprocating motion at the pitch point. Dynamic testing revealed predictable oscillatory bearing forces with a 45% amplitude variation, making them suitable for vibration-driven applications. Originality/value This study presents an original gear design that integrates motion conversion and power transmission. Its primary novelty is the AM-driven framework, proving DLP's capability to manufacture such innovative components. These findings demonstrate the gears’ suitability for vibration-driven applications such as medical devices, robotics, high-precision control systems, positive displacement pumps and vibration motors that require smooth motion transfer and cyclic dynamics.