Optimal Design of a Stewart–Gough Platform for Multidirectional 3-D Printing

The existing 3-D printing techniques have several disadvantages such as aliasing and difficulty in building around inserts due to limited motions associated with the equipment. The limitation of build direction results in poor surface finish due to aliasing (or layer stair-stepping) and adverse material properties in certain directions which limits use of 3-D printing for many industrial applications. The present study investigates the application of Parallel Kinematic Machines (PKMs) in achieving multidirectional 3-D printing. The proposed architecture addresses some of the limitations of existing Fused Deposition Modelling (FDM)-based 3-D printer by allowing six-axis motions between extruder and platform while building the component. The study explores the application of Stewart–Gough Platform (SGP) further for 3-D printing and illustrates its capability as a viable solution for multi-axis FDM. The design of SGP for multidirectional FDM is realized for optimal dexterity using bulk dexterity index. The study discusses details of the optimization formulation and consequent results associated with the same. A conceptual design of the SGP is subsequently proposed based on the results of the optimization. The proposed SGP-based machine architecture is expected to offer advantages such as improved surface finish and control of directional properties, which signifies push towards freeform fabrication using multidirectional 3-D printing.