Harnessing Magnets to Design Tunable Architected Bistable Material

Abstract

A new type of tunable bistable metamaterial (TBM) is proposed which is made by embedding magnets into the flexible cellular bistable materials with double tilted beams. To find out the effect of magnets on the mechanics of TBM, several samples are fabricated and magnets with different residual flux density, which is used to describe the magnetic field strength, are embedded. Quasi-static uniaxial compression tests are performed and the results show that the bistability of the TBM is successfully adjusted by embedding magnets. Furthermore, both numerical and analytical simulations are carried out to further understand the bistable property and energy absorption ability of the proposed metamaterial.

Magnetically Assisted Rotationally Multistable Metamaterials for Tunable Energy Trapping–Dissipation

“…This strategy has long been used in the field of vibration control. [28][29][30][31] However, in recent years, there has been a growing interest in utilizing such magnetic systems in tandem with mechanical elements to realize exotic mechanical behavior, such as simultaneous negative stiffness and negative Poisson's ratio, [32,33] to improve tunability of mechanical properties, [34,35] and to expand energy trapping capability of multistable materials. [36,37] Most recently, this technique has been exploited to realize magnetoelastic shape reconfigurable metamaterials with improved hysteretic behavior and tunable wave filtering characteristics.…”

Magnetically Controlled Soft Robotics Utilizing Elastomers and Gels in Actuation: A Review

“…Our recent Review provides summaries on the macromolecular origin of the toughness of elastomer and gels, as well as on the key material properties that are important in soft robotics applications. [8] Elastomers and gels can become magnetically responsive by attaching/incorporating permanent magnets [33] or magnetic coils [34] or by dispersing magnetic particles and/or ferrofluid in the material. [35] The former method is simpler and resulting magnetism is more straightforward to analyze, but both permanent magnets and magnetic coils are considerably stiffer and more brittle in nature compared with elastomers and gels.…”

“…[8] Magnetic soft actuators are adapting the concept of folding, instability, and bistability to enable rapid shape transformation with high output power ( Figure 2c). [33,96,97] Zhao and coworkers fabricated various magnetically deployable 3D structures by controlling the local orientation of ferromagnetic domains by a novel 3D printing method. [98] In this work, the authors defined the direction of magnetic domains by aligning the polarity of the ferromagnetic NdFeB particles in a strong magnetic field at the moment of 3D printing, immediately followed by curing the silicone matrix to fix the magnetic domains (Figure 2e).…”

Harnessing Friction in Intertwined Structures for High‐Capacity Reusable Energy‐Absorbing Architected Materials

“…A well‐investigated mechanism is mechanical instability of micro‐cells, such as buckling of flexible beams [ 30 , 31 , 32 ] and shells, [ 33 ] and nonlinear forces between magnets. [ 34 , 35 ] The assembled structures, obtained by connecting a series of these micro‐cells, often produce hysteric saw‐tooth force–displacement curves. [ 36 , 37 ] The metamaterials constructed in this way are reusable since the deformation is elastic.…”