3D Bioplotter Research Papers

Displaying all papers about Soft Robotics (8 results)

Topology-Optimized 4D Printing of a Soft Actuator

Acta Mechanica Solida Sinica 2019

Soft robots and actuators are emerging devices providing more capabilities in the field of robotics. More flexibility and compliance attributing to soft functional materials used in the fabrication of these devices make them ideal for delivering delicate tasks in fragile environments, such as food and biomedical sectors. Yet, the intuitive nonlinearity of soft functional materials and their anisotropic actuation in compliant mechanisms constitute an existent challenge in improving their performance. Topology optimization (TO) along with four-dimensional (4D) printing is a powerful digital tool that can be used to obtain optimal internal architectures for the efficient performance of porous soft actuators….

System identification and robust tracking of a 3D printed soft actuator

Smart Materials and Structures 2019 Volume 28, Article 075025

Current three-dimensional (3D) printing allows for the fabrication of controllable 3D printed soft actuators with growing applications in soft robotics, like cell manipulation and drug delivery. Therefore, a precise and computationally efficient control algorithm for robust trajectory tracking of the 3D printed soft actuators has become important. The results of the primary model of the soft actuator deviated from experimental results due to uncertainties such as time-varying characteristics of the actuator. Hence, a second-order type nonsingular terminal sliding mode controller (NTSMC) for robust stabilization and trajectory tracking of the 3D printed actuator is proposed. It is shown via experiments that…

Wet 3‐D printing of epoxy cross‐linked chitosan/carbon microtube composite

Polymers for Advanced Technologies 2019

Over the last decays, the use of conductive biopolymer composites has been growing in areas such as biosensors, soft robotics, and wound dressing applications. They are generally soft hydrophilic materials with good elastic recovery and compatible with biological environments. However, their application and removal from the host are still challenging mainly due to poor mechanical strength. This work displays a technique for the fabrication of complex‐shaped conductive structures with improved mechanical strength by wet three‐dimensional (3‐D) printing, which uses a coagulation bath to quickly solidify an epoxy cross‐linked chitosan/carbon microtube composite ink. The fabricated conductive structure demonstrated higher elongation strength…

Nanogrooved carbon microtubes for wet 3D printing of conductive composite structures

Polymer International 2019

Recent advances in 3D printing have enabled the fabrication of interesting structures which were not achievable using traditional fabrication approaches. 3D printing of carbon microtube composite inks allows fabrication of conductive structures for practical applications in soft robotics and tissue engineering. However, it is challenging to achieve 3D printed structures from solution‐based composite inks which requires an additional process to solidify the ink. Here, we introduce a wet 3D printing technique which uses a coagulation bath to fabricate carbon microtube composite structures. We show that through facile nanogrooving approach which introduces cavitation and channels on carbon microtubes, enhanced interfacial interactions…

Rigid elements dynamics modeling of a 3D printed soft actuator

Smart Materials and Structures 2019 Volume 28, Issue 2, Article 025003

Due to the growing interest in three-dimensional (3D) printed soft actuators, the establishment of an appropriate mathematical model that could effectively predict the actuators’ dynamic behavior has become necessary. This study presents the development of an effective modeling strategy for the dynamic analysis of a 3D printed polyelectrolyte actuator undergoing large bending deformations. The proposed model is composed of two parts, namely electrical and mechanical dynamic models. The electrical model describes the actuator as a gray box model, whereas the mechanical model relates the stored charges to the bending displacement through considering the printed actuator as a discretized system connected…

Polyelectrolyte Soft Actuators: 3D Printed Chitosan and Cast Gelatin

3D Printing and Additive Manufacturing 2018 Volume 5, Issue 2, Pages 138-150

With increasing utilization of robots in daily tasks, especially in biomedical and environmental monitoring applications, there would be demands for soft, biodegradable, or even edible actuators that provide more versatility than conventional rigid materials (e.g., metals and plastics). Polyelectrolyte hydrogels produce mechanical motion in response to electrical stimulus, making them good candidates for implementation of soft actuators. However, their conventional fabrication process has so far hindered their applicability in a broad range of controlled folding behaviors. A novel application of 3D printing in biodegradable and biocompatible soft robots is presented in this study. It is observed that the contactless electroactive…

Reversible Programing of Soft Matter with Reconfigurable Mechanical Properties

Advanced Functional Materials 2017 Volume 27, Issue 13 Article 1605665

Biology uses various cross-linking mechanisms to tailor material properties, and this is inspiring technological efforts to couple independent cross-linking mechanisms to create hydrogels with complex mechanical properties. Here, it is reported that a hydrogel formed from a single polysaccharide can be triggered to reversibly switch cross-linking mechanisms and switch between elastic and viscoelastic properties. Specifically, the pH-responsive self-assembling aminopolysaccharide chitosan is used. Under acidic conditions, chitosan is polycationic and can be electrostatically cross-linked by sodium dodecyl sulfate (SDS) micelles to confer viscoelastic and self-healing properties. Under basic conditions, chitosan becomes neutral, the electrostatic SDS–chitosan interactions are no longer operative, and…

Printed ionic-covalent entanglement hydrogels from carrageenan and an epoxy amine

RSC Advances 2014 Volume 4, Issue 72, Pages 38088-38092

Carrageenan/epoxy amine ionic-covalent entanglement hydrogels were fabricated on a 3D printer. The thermal gel transition behaviour of the biopolymer kappa-carrageenan was exploited to fix the shape of the patterned ink until a covalent polymer network formed by epoxy amine addition chemistry. The printed hydrogels display a work of extension value of 1.4 ± 0.3 MJ m−3.