Design optimization and one-shot 3D printing of a bio-inspired soft robot capable of counter-flexural motion at low actuation pressures
Luca DI LEO, Alessio PRICCI, Andrea GRAVILI, Gianluca PERCOCO
Abstract. This work presents the design, fabrication, and numerical analysis of a soft actuator with counter-flexural motion fabricated in thermoplastic polyurethan (TPU), aiming at mimicking the serpentine movement of snakes. Printing parameters were chosen to allow the one-shot 3D printing of the soft robot, ensuring its air tightness up to 200 [kPa]. The hyperelastic behavior of TPU was characterized by means of uniaxial tensile tests of samples produced with the abovementioned optimal printing settings. Non-linear finite element simulations were conducted to perform a design optimization of the pneumatic chambers; the purpose is to minimize the actuation pressure needed to achieve a prescribed bending. The experimentally measured deflections were compared with numerical results, showing a very good agreement. Practical relapses are in the field of medical devices where the proposed low-pressure actuated design will allow safer human-robot interactions.
Keywords
Material Extrusion, Product Design, Virtual Modeling
Published online 9/10/2025, 9 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Luca DI LEO, Alessio PRICCI, Andrea GRAVILI, Gianluca PERCOCO, Design optimization and one-shot 3D printing of a bio-inspired soft robot capable of counter-flexural motion at low actuation pressures, Materials Research Proceedings, Vol. 57, pp 583-591, 2025
DOI: https://doi.org/10.21741/9781644903735-68
The article was published as article 68 of the book Italian Manufacturing Association Conference
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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