Strength Test and Analysis of Additive Manufactured Gears and Their Applicability for Explosive Ordnance Disposal Robots

Sean T. Murphy


Recent advancements in additive manufacturing have led to a number of fields within the Department of Defense employing this technology. This research determines if additive manufacturing can assist the field of explosive ordnance disposal by manufacturing replacement gears for the micro tactical ground robot. This is accomplished by completing a single-tooth bending test on a number of gear teeth manufactured using two different 3D printers. The ProJet 3500, a $90,000 material-jetting printer, produced gear teeth that proved to be of high strength and quality. The Lulzbot Taz 6, a $2,500 material-extrusion printer, also produced strong gear teeth, but lacked quality dependent on build orientation. The research shows the orientation of layers affected the strength of the gear teeth, but not to a point where the tooth failed before reaching a pre-calculated, required stress. This work provides a starting point for understanding the effect of layering on additive manufactured gears while providing strong evidence toward the efficacy of additive manufacturing within the field of explosive ordnance disposal.