Abstract
A bistable response is an innate feature of tensegrity metamaterials, which is a conundrum to attain in other metamaterials, since it ushers unconventional static and dynamical mechanical behaviors. This paper investigates the design, modeling, fabrication and testing of bistable lattices with tensegrity architecture and nanoscale features. First, a method to design bistable lattices tessellating tensegrity units is formulated. The additive manufacturing of these structures is performed through multiphoton lithography, which enables the fabrication of microscale structures with nanoscale features and extremely high resolution. Different modular lattices, comprised of struts with 250 nm minimum radius, are tested under loading-unloading uniaxial compression nanoindentation tests. The compression tests confirmed the activation of the designed bistable twisting mechanism in the examined lattices, combined with a moderate viscoelastic response. The force-displacement plots of the 3D assemblies of bistable tensegrity prisms reveal a softening behavior during the loading from the primary stable configuration and a subsequent snapping event that drives the structure into a secondary stable configuration. The twisting mechanism that characterizes such a transition is preserved after unloading and during repeated loading-unloading cycles. The results of the present study elucidate that fabrication of multistable tensegrity lattices is highly feasible via multiphoton lithography and promulgates the fabrication of multi-cell tensegrity metamaterials with unprecedented static and dynamic responses.
Highlights
The inexorable advances in materials science have been accomplished and conflated with the progress of additive manufacturing (AM) technologies over the recent years
An intriguing category of lattice metamaterials is that of tensegrity frameworks: prestressed pin-connected lattices composed of bars and cables, which typically feature internal mechanisms
The bistable response of tensegrity structures made of three-dimensional assembles of tensegrity prisms was investigated in microscale structures equipped with nanoscale features
Summary
The inexorable advances in materials science have been accomplished and conflated with the progress of additive manufacturing (AM) technologies over the recent years. Tensegrity structures exhibit different types of nonlinear static and dynamic responses, depending on their connectivity, geometry and state of selfstress [33,34,35]. Some tensegrity modules can transcend from one stable state to two other stable states, either by changing the lengths of their elements or by changing the selfstress level [39]. This bistable response has been observed in some case studies at the macroscopic scale [40,41]. It can be expediently utilized to develop tunable, switchable and/or reconfigurable metamaterials, which are able to support solitary wave dynamics [42]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
