Design of a programmable particle filtering medium using a novel auxetic metamaterial

Abstract

This manuscript aims to design and develop a 2D auxetic filtering medium with programmable geometric features specifically designed to vary under in-plane tensile strain. This feature empowers the filtering medium to control the particles separation. A novel design and optimisation algorithm developed in Matlab® determines the final optimized geometry of the filtering medium based on the desired particle size input. Upon thorough numerical investigation, an empirical relationship between the linear elastic in-plane tensile strain and aperture size of the proposed metamaterial is revealed. This empirical relation can be used in mechatronic and control systems to steer the proposed filtering medium. A prototype of such filtering medium capable of classification of particles of size 4mm to 4.5mm, when subjected to linear strain, is fabricated through Fused Deposition Modelling (FDM) process. The developed geometry configurations in this research are scalable, providing a potential cost-effective and efficient solution for industrial applications including reconfigurable filtration and segregation systems.

Multi-Objective Parametric Shape Optimisation of Body-Centred Cubic Lattice Structures for Additive Manufacturing

“…Given its ability to tackle complex optimisation problems, for instance, where there is a high chance of falling into a local minima during the optimisation process, or when the problem involves optimising multiple conflicting objectives, the GA serves as a strong tool in the pursuit of optimal solutions [35]. The GA has been implemented in several previous studies focused on the design of AM, such as the optimisation of auxetic metamaterials [23] and the material optimisation of biomedical composite devices [36].…”

“…Topology optimisation techniques [20] can be utilised to find the best material distribution, member connectivity, or position of the holes within a lattice unit cell [21]. In contrast, shape optimisation techniques aim to determine the best shape for a structure, while topology, i.e., the connectivity of the strut members within the unit cell, remains unchanged throughout the optimisation process [22,23] as demonstrated in Figure 1b for a BCC structure. Parametric shape optimisation is a subset of shape optimisation that specifically focuses on varying a predefined set of geometric parameters to optimise the design's performance.…”

Reversible negative compressibility metamaterials inspired by Braess’s Paradox

“…demonstrate novel properties not exhibited by most natural and artificial materials. These properties are usually reversal of common senses, such as negative Poisson's ratio [1,2], negative stiffness [3,4], negative swelling behavior [5], and negative refraction [6,7]. Furthermore, some studies demonstrated how to tune or induce the properties of metamaterials after they are manufactured using temperature [8][9][10], magnetic fields [11], air pressure [12], and other methods, thus achieving more diverse applications.…”

A flexible metamaterial absorber with temperature-insensitive design at microwave frequencies

“…Moreover, flexible MAs have gained considerable interest due to their advantages, including flexible design, simple processing, and broadband absorption capability [2,[21][22][23][24]. MA refers to an artificial composite structure or material that embeds specific unit structures into traditional materials, thereby creating extraordinary physical properties that natural materials lack [25][26][27]. The periodic arrangement of these units allows for tunability of polarization, EM wave propagation, and equivalent EM parameters [28][29][30].…”