A Pose Control Algorithm for Elbow Models Based on Five-Axis Unsupported 3D Printing

Orthopedic emergency interventions necessitate swift brace production. Utilizing 3D printing technology, expedited fabrication of tailored braces becomes feasible. Nonetheless, the considerable number of suspended structures in elbow braces impedes efficient printing. The five-degree-of-freedom unsupported 3D printing technique, integrated with a rotating base plate, addresses this efficiency concern. Following a field 3D scan, the irregular elbow model's position and orientation must align with the printing mechanism for seamless execution. To tackle the challenge of optimal pose adaptation for the elbow model, a strategy grounded on 3D elbow model characteristics and printing device structural constraints was introduced. Given the non-uniformity of the 3D scanned model, the model's spatial pose attributes were determined by extracting the elbow model's central line, computing the inter-axis angles, and distinguishing between the major and minor axes. Considering the rotation angle restrictions of the printer's base plate and the coordinate placement of the model's foundation point, various aspects of the support model's pose, including its parallel base surface, spatial orientation, and proximity to the base plate, were meticulously calibrated to suit 3D printing requirements. Comparative simulation analyses and print tests confirm the efficacy of the elbow model's automatic adjustment method, advancing the cause of rapid 3D slicing devoid of external support.