Toward a New Generation of Electrically Controllable Hygromorphic Soft Actuators

Taccola, Silvia; Greco, Francesco; Sinibaldi, Edoardo; Mondini, Alessio; Mazzolai, Barbara; Mattoli, Virgilio

doi:10.1002/adma.201404772

Cited by 279 publications

(261 citation statements)

References 29 publications

Supporting

Mentioning

258

Contrasting

Unclassified

Order By: Relevance

“…Speed, reversibility, large-scale deformations and, most importantly, the control over the direction of movement is desired in order to make synthetic replicas inspired from natural materials or otherwise. Although innovative concepts for polymeric actuation triggered by, for example, electrical stimulation, [1][2][3] light, [4][5][6] magnetic fi eld, [ 7 ] pH, [ 8 ] humidity and water, [9][10][11][12][13] and many others [ 14,15 ] are shown covering the last few years, a polymeric synthetic actuator with control in direction of movement and reversible change in shapes at high speed is still awaited. The pioneering work of Hu et al [ 16 ] regarding actuation based on differential swelling/shrinking of two layers triggered by water and temperature in a bilayer polymeric system remains the basis of thermoresponsive polymeric actuators, highly interesting for applications in tissue engineering, cell High porosity was utilized in providing fast actuation to polymeric actuators with acetone, camphor sulphonic acid, ethanol, and sodium hydroxide as solvents.…”

Section: Introductionmentioning

confidence: 99%

Giving Direction to Motion and Surface with Ultra‐Fast Speed Using Oriented Hydrogel Fibers

Liu

Jiang

Sun

et al. 2015

Adv Funct Materials

129

100

View full text Add to dashboard Cite

Thermoresponsive hydrogel fibrous membranes showing directionally controlled movements and surface change with ultra‐fast speed are presented for the first time. They show reversible coiling, rolling, bending, and twisting deformations in different controllable directions for many cycles (at least 50 cycles tried) with inside‐out change in surfaces and shapes. Speed, reversibility, large‐scale deformations and, most importantly, control over the direction of deformation is required in order to make synthetic actuators inspired from natural materials or otherwise. A polymeric synthetic material combining all these properties is still awaited. This issue is addressed and provide a very simple system fulfilling all these requirements by combining porosity and asymmetric swelling/shrinking via orientation of hydrogel fibers at different angles in a fibrous membrane. Electrospinning is used as a tool for making membranes with fibers oriented at different angles.

show abstract

Section: Introductionmentioning

confidence: 99%

Giving Direction to Motion and Surface with Ultra‐Fast Speed Using Oriented Hydrogel Fibers

Liu

Jiang

Sun

et al. 2015

Adv Funct Materials

129

100

View full text Add to dashboard Cite

show abstract

“…The fulfilment of these criteria depends on the ability of the active layer to produce substantial hygroexpansion and generate enough force to drive the curvature changes of the composites. Wood is one of few natural hygroscopic materials which encompasses these characteristics and, in fact, greatly surpasses the combination of strength and magnitude and speed of moisture-induced response achievable with many synthetic alternatives [27], such as hydrogels [23], electro-active and layer-by-layer deposited hygroscopic polymers [28,29] and bacterial spores [30]. This points to good potential for application of wood for active layers of large-scale hygromorphs.…”

Section: Wood Versus Synthetic Active Layersmentioning

confidence: 99%

Section: Conclusion and Recommendations For Future Researchmentioning

confidence: 99%

“…Over the last 20 years, the research on biomimetic moisture-responsive composites has advanced rapidly from the identification of the opening mechanism of pine cones in 1997 [20], the development of man-made bilayer responsive materials [19,22] in 2009, and more recently widespread research into synthetic hygromorphs [23,[27][28][29][30] and tentative steps towards application [26,27,39]. Within existing published work, details of fabrication techniques, material response over multiple cycles, durability, and response to external weathering are scarce and we have sought to address this gap in available knowledge.…”

Section: Conclusion and Recommendations For Future Researchmentioning

confidence: 99%

See 1 more Smart Citation

Sustainable Materialisation of Responsive Architecture

2017

View full text Add to dashboard Cite

Natural organisms which employ inherent material properties to enable a passive dynamic response offer inspiration for adaptive bioclimatic architecture. This approach allows a move away from the technological intensity of conventional "smart" building systems towards a more autonomous and robust materially embedded sensitivity and climatic responsiveness. The actuation mechanisms of natural responsive systems can be replicated to produce artificial moisture-sensitive (hygromorphic) composites with the response driven by hygroexpansion of wood. The work presented here builds on previous research on lab-scale material development, to investigate in detail the applicability of wood-based hygromorphic materials for large-scale external applications. The suitability of different material production techniques and viability of potential applications is established through a detailed programme of experimentation and the first one-year-long durability study of hygromorphic wood composites in full weathering conditions. These results provide the basis for the design of an optimised responsive cladding system. The opportunities and challenges presented by building integration and architectural functionalisation of responsive wood composites are discussed based on a hierarchy of application typologies including functional devices and components, performance-oriented adaptive systems, the value of aesthetic and spatial experience and place-specific contextual integration. The design of the first full-scale building application of hygromorphic wood composites is presented.Keywords: hygromorphic wood composite; durability; fabrication; biomimetic design; adaptive facade; sustainable architecture; passive building design Re-Shaping Adaptive Architecture with Responsive Wood Composites Ecologically Embedded versus Technologically Imposed ResponseThe accepted notion of a modern building is inextricably connected with the expectations of permanence and stability from both the structure and the interior climate, defying the natural variations of the external environment. In this context, a conventional building envelope is given the role of a barrier between the controlled interior space and transient outdoor conditions [1]. In contrast to traditional vernacular architecture, which has commonly been designed to employ the local climatic conditions, such as daylight and solar thermal radiation [2-4], modern buildings, often featuring extensively glazed facades, tend rely heavily on artificial heating, ventilation and air conditioning (HVAC) to maintain the desired interior comfort [5,6]. This overreliance on active (i.e., energy-dependent) building systems impacts energy performance of buildings during their operation, which accounts for approximately 80%-90% of the total energy consumed during their lifecycle [7,8].

show abstract

“…In [192], PPy petal actuators integrated into a flexible membrane for increased actuation performance were combined with flap check valves in a PDMS-based device to fabricate a reciprocating micropump with a maximum flow rate of 1.26 ml/min at an actuation voltage of 4 V. Furthermore, a physics-based control-oriented model was developed to predict membrane deformation and flow rate in response to the electric field stimulation of the CP actuator. Taccola et al [193] have recently proposed using the hygroscopic nature of CP concurrently with its electrical conductivity for a new class of soft actuators. They discovered that CP films change their volume reversibly due to the absorption and desorption of water from vapor in air.…”

Section: Conjugated Polymersmentioning

confidence: 99%

Stimulus-active polymer actuators for next-generation microfluidic devices

Hilber

2016

Appl. Phys. A

View full text Add to dashboard Cite

Microfluidic devices have not yet evolved into commercial off-the-shelf products. Although highly integrated microfluidic structures, also known as lab-on-a-chip (LOC) and micrototal-analysis-system (lTAS) devices, have consistently been predicted to revolutionize biomedical assays and chemical synthesis, they have not entered the market as expected. Studies have identified a lack of standardization and integration as the main obstacles to commercial breakthrough. Soft microfluidics, the utilization of a broad spectrum of soft materials (i.e., polymers) for realization of microfluidic components, will make a significant contribution to the proclaimed growth of the LOC market. Recent advances in polymer science developing novel stimulus-active soft-matter materials may further increase the popularity and spreading of soft microfluidics. Stimulus-active polymers and composite materials change shape or exert mechanical force on surrounding fluids in response to electric, magnetic, light, thermal, or water/solvent stimuli. Specifically devised actuators based on these materials may have the potential to facilitate integration significantly and hence increase the operational advantage for the end-user while retaining costeffectiveness and ease of fabrication. This review gives an overview of available actuation concepts that are based on functional polymers and points out promising concepts and trends that may have the potential to promote the commercial success of microfluidics.

show abstract

Toward a New Generation of Electrically Controllable Hygromorphic Soft Actuators

Cited by 279 publications

References 29 publications

Giving Direction to Motion and Surface with Ultra‐Fast Speed Using Oriented Hydrogel Fibers

Giving Direction to Motion and Surface with Ultra‐Fast Speed Using Oriented Hydrogel Fibers

Sustainable Materialisation of Responsive Architecture

Stimulus-active polymer actuators for next-generation microfluidic devices

Contact Info

Product

Resources

About