Research Article
No access
Published Online: 1 March 2018

Production Techniques for 3D Printed Inflatable Elastomer Structures: Part II—Four-Axis Direct Ink Writing on Irregular Double-Curved and Inflatable Surfaces

Publication: 3D Printing and Additive Manufacturing
Volume 5, Issue Number 1


This article is the second in a two-part series describing a process for conformal 3D printing onto inflated substrates. The article describes the design and build of a custom-built four-axis 3D printer with the ability to measure the shape of any uneven substrate, and to then accurately extrude a thixotropic silicone onto the substrate by using Direct Ink Writing techniques. Details of strategies for 3D scanning a double-curved tubular inflated substrate using an industrial triangulation laser measurement device are given. Methods to import scan data and create a digital representation of the surface within the parametric design software Grasshopper 3D are explained. Geodesic print paths are created over the surface of the computed substrate, and these are the basis for calculating 3D printer toolpaths. A constant surface linear velocity strategy is developed, allowing the printer to move the print nozzle at a varying speed over the substrate surface. The change in speed is correlated with changes in the surface linear velocity of a fourth axis rotation of the variable radius balloon substrate. This ensures that the extruded bead maintains a constant thickness, even while using a constant flow rate deposition. The process is achieved by adapting cartographic techniques to re-project to the desired print paths. The efficacy of this technique is analyzed by 3D scanning a printed patterned balloon, then measuring and comparing multiple cross-sections of the extruded beading.

Get full access to this article

View all available purchase options and get full access to this article.


Chakraborty D, Reddy BA, Choudhury AR. Extruder path generation for curved layer fused deposition modeling. Comput Aided Des 2008;40:235–243.
Diegel O, Singamneni S, Huang B, Gibson I. Getting rid of wires: curved layer fused deposition modelling in conductive polymer additive manufacturing. Key Eng Mater 2011;467–469:662–667.
Singamneni S, Roychoudhury A, Diegel O, Huang B. Modelling and evaluation of curved layer fused deposition. J Mater Process Technol 2012;212:27–35.
Allen RJA, Trask RS. An experimental demonstration of effective curved layer fused filament fabrication utilising a parallel deposition robot. Addit Manuf 2015;8:78–87.
Adams JJ, Duoss EB, Malkowski TF, Motala MJ, Ahn BY, Nuzzo RG, et al. Conformal printing of electrically small antennas on three-dimensional surfaces. Adv Mater 2011;23:1335–1340.
Coulter FB, Ianakiev A. 4D printing inflatable silicone structures. 3D Printing and Addit Manuf 2015;2:140–144.
Bausch N, Dawkins DP, Frei R, Klein S. 3D printing onto unknown uneven surfaces. 7th IFAC Symposium on Mechatronic Systems, MECHATRONICS 2016: Loughborough University, Leicestershire, UK, September 5-8, 2016; pp. 583–590.
Lith RV, Baker E, Ware H, Yang J, Farsheed AC, Sun C, et al. 3D-printing strong high-resolution antioxidant bioresorbable vascular stents. Adv Mater Technol 2008; 1:1600138.
Soleimani M, Menon C. Preliminary investigation of a balloon shaped actuator based on electroactive elastomers. Smart Mater Struct 2010;19:047001.
Petralia MT, Wood R. Fabrication and analysis of dielectric-elastomer minimum-energy structures for highly-deformable soft robotic systems. Intelligent Robots and Systems (IROS), 2010 IEEE/RSJ International Conference on, pp. 2357–2363, 2010.
Peele BN, Wallin TJ, Zhao H, Shepherd RF. 3D printing antagonistic systems of artificial muscle using projection stereolithography. Bioinspir Biomim 2015;10:5.
Murphy SV, Atala A. 3D bioprinting of tissues and organs. Nat Biotechnol 2014;32:773–785.
Muth JT, Vogt DM, Truby RL, Mengüç Y, Kolesky DB, Wood RJ, et al. Embedded 3D printing of strain sensors within highly stretchable elastomers. Adv Mater 2014;26:6307–6312.
Choi Y, Banarjee A. Tool path generation and tolerance analysis for free form surfaces. Machine Tools Manuf 2007;47:689–696.
Czerech L. Selection of optimal machining strategy in the manufacture of elements bounded by curvilinear surfaces. Acta Machanica et Automatic. 2013;7:5–9.
Lazoglu I, Manav C, Murtezaoglo Y. Tool path optimization for free form surface machining. CIRP Ann 2009;58:101–104.
Ding S, Mannan MA, Poo AN, Yang DCH, Han Z. Adaptive iso-planar tool path generation for machining of free form surfaces. Comput Aided Des 2003;35:141–153.
Elber G, Cohen E. Tool Path generation for freeform surface models. Comput Aided Des 1994;26:61–76.
Acosta D, Garcia O, Aponte J. Laser triangulation for shape acquisition in a 3D scanner plus scan. Electronics, Robotics and Automotive Mechanics Conference, 2006;2:14.
Cui Y, Schuon S, Chan D, Thrun S, Theobalt C. 3D Shape Scanning with a Time-of-Flight Camera. 2010 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, San Francisco, CA, 2010; pp. 1173–1180.
Rocchini C, Cignoni P, Montani C, Pingi P, Scopigno R. A low cost 3D scanner based on structured light. Comput Graph Forum 2001;20:299–308.
Maffei R, Luchsinger RH, Zanelli A. Design tools for inflatable structures. Proceedings: International Conference on Textile Composites and Inflatable Structures; Barcelona, Spain, October 5–7, 2011.
Datasheet for Banner LQ10., accessed August 2017.
Marlin Firmware., accessed August 2017.
Grasshopper 3D., accessed August 2017.

Information & Authors


Published In

cover image 3D Printing and Additive Manufacturing
3D Printing and Additive Manufacturing
Volume 5Issue Number 1March 2018
Pages: 17 - 28


Published in print: March 2018
Published online: 1 March 2018


Request permissions for this article.




Fergal B. Coulter
Department of Mechanical and Materials Engineering, University College Dublin, Dublin, Ireland.
Department of Materials, ETH, Zurich, Switzerland.
Brian S. Coulter
Soils and Analytical Services Department, Teagasc, Johnstown Castle Research Centre, Wexford, Ireland.
Emmanouil Papastavrou
School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom.
Anton Ianakiev
School of Architecture, Design and Built Environment, Nottingham Trent University, Nottingham, United Kingdom.


Opposite page: Auxetic chiral pattern printed on an inflated balloon surface, using direct ink writing of silicone. Photo credit: Fergal Coulter.
Address correspondence to:Fergal B. CoulterDepartment of Mechanical and Materials EngineeringUniversity College DublinBelfieldDublin D4Ireland
E-mail: [email protected]

Author Disclosure Statement

No competing financial interests exist.

Metrics & Citations



Export citation

Select the format you want to export the citations of this publication.

View Options

Get Access

Access content

To read the fulltext, please use one of the options below to sign in or purchase access.

Society Access

If you are a member of a society that has access to this content please log in via your society website and then return to this publication.

Restore your content access

Enter your email address to restore your content access:

Note: This functionality works only for purchases done as a guest. If you already have an account, log in to access the content to which you are entitled.

View options


View PDF/ePub

Full Text

View Full Text







Copy the content Link

Share on social media

Back to Top