3D Bioprinting Soft Actuators: Multiple Materials & Topology Optimization

Share this Article

In the recently published ‘Effects of Topology Optimization in Multimaterial 3D Bioprinting of Soft Actuators,’ international researchers delve further into the fabrication of soft robotics, bordering on the 4D as they look for ways to develop improved polymers able to respond to outer stimuli.

3D printing and robotics are common partners these days, whether researchers are refining tools like grippers, developing new frameworks, or creating ultra-programmable robotics. The authors point out that production of robotics is easier thanks to digital fabrication, and especially as parts can be created in one single piece without requiring arduous assembly later. Researchers are also beginning to rely more on 4D printing of materials that can deform and then return back to their initial shape:

“The recent proliferation of four-dimensional-printed soft robots stems from both developments in the additive manufacturing and research in responsive materials.”

In this study, the authors focused on actuation performance, employing finite element analysis (FEA) and topology optimization (TO) for better design to also transfer to other soft robotic systems.

Computer-aided design models of the actuators (A) two-material three-dimensional printing, (B) mechanical forces and boundary constraints

“The TO modeling for the soft actuator was based on the [solid isotropic material with penalization] SIMP approach and the design goal set to minimum strain energy or maximum stiffness with optimal structural configuration. To control the actuator stiffness and the optimization convergence, a volume constraint was set,” stated the researchers.

The team used two materials for fabricating the optimized lattice, creating boundaries based on a cantilever beam with distributed force.

Two-material topology optimization layers’ configuration of bioprinted actuator

While numerous other techniques have been explored regarding hydrogels, in this study the researchers relied on the liquid hardening method for chitosan hydrogel. The 3D printed pastes varied in molecular weight as well as concentrations.

(A) Three-dimensional bioprinting; (B) two-material topology optimized bioprinted actuators.

Efficiency of the two-material TO was displayed as the research team performed numerous experiments, finding that the multi-material approach resulted in better bending performance.

(A) Bending index of the actuator and (B) the measurement set up.

“The main cause of smaller bending amplitude in our sample is attributed to the characteristic of polyelectrolyte hydrogel actuators that are highly dependent on electrical stimulus and once the input signal is turned off, there is a back relaxation in bending,” stated the researchers. The lack of 3D printing fidelity for certain extrudate systems may reduce the improvement predicted by TO mainly due to the open loop process of 3D printing. In the current systems, there is no feedback control on the printing process parameters to compensate for uncertainties during 3D printing. The lack of precise control in factors such as ambient temperature, moisture, and instrument vibrations could lead to imperfect representation of the TO model. Further, research in optimizing the 3D printing of stimuli-responsive hydrogels in conjunction with TO could result in significant functionality enhancement of bioprinted actuators.

“The results demonstrate the efficacy of multimaterial TO-based design to bring about the full potential of the performance of bioprinted soft actuators,” concluded the researchers.

What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.

[Source / Images: ‘Effects of Topology Optimization in Multimaterial 3D Bioprinting of Soft Actuators’]

Share this Article


Recent News

3D Printing Webinar and Virtual Event Roundup: November 29, 2020

3D Printing News Briefs, November 28, 2020: Thinking Huts, nScrypt, Alloyed, ASTM International



Categories

3D Design

3D Printed Art

3D Printed Food

3D Printed Guns


You May Also Like

Australian Navy Starts Pilot Program with Large-Format WarpSPEED Metal 3D Printer

Australian metal 3D printing company SPEE3D, based in both Darwin and Melbourne, specializes in large-format additive manufacturing, and says that its technology is the fastest and most economical metal AM...

Interview: Satori and Moroccan Designer 3D Print “Work From Home” Office Goods

London-based startup Satori, which means “enlightenment” in Japanese Zen, recently entered the 3D printing market with the launch of its new professional 3D printer, the compact, resin-based ST1600. The system,...

2020’s Inside 3D Printing Seoul Online-Offline Conference: What Was it Like?

When the SARS-CoV-2 virus hit early this year, few of us could guess the scope and scale of the resulting pandemic, and how it would disrupt every aspect of daily...

Authentise Integrating nebumind’s Digital Twin Visualization into AMES 3D Printing Software

Authentise, which offers data-driven process automation software and workflow tools for AM, announced that it is partnering with German software startup nebumind for the purposes of integrating the digital twin...


Shop

View our broad assortment of in house and third party products.