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Rowing is a sport that requires athletes to perform the action of pulling and rotating an oar by hand, applying forces of considerable magnitude. Herein, inspired by the notion that auxetic materials and metamaterials behave differently compared to their conventional counterparts, it is examined how a handle prototype, specifically designed to incorporate the classic re‐entrant motif, behaves and how end‐users perceive it. Physical experiments conducted on such prototype, which measured the contact pressures, suggest that on average, higher pressures are measured when pulling with this reentrant grip compared to its non reentrant counterpart, indicating that this re‐entrant prototype should feel firmer. More importantly, respondents of a survey are asked to give their feedback, and different views on which handle they would prefer to use are provided. The ones who preferred the prototype with the reentrant features report that they preferred it because it felt firmer and allowed for a better grip. This suggests that there is potential for further investigation into whether handles, oar handles in particular, made from auxetic components, re‐entrant cells, or other motifs which are well known for their negative Poisson's ratio characteristics, could provide a better and more secure grip and be used in sports applications. [ABSTRACT FROM AUTHOR]

Auxetics display the anomalous property of expanding laterally when uniaxially stretched, that is, a negative Poisson's ratio, a property that arises from 1) the presence of specific geometric features within the nano/macrostructure of the material and 2) amenable deformations in response to the applied stimulus. Herein, how ancient symmetrical esthetic artifacts have been transformed to functional auxetics through mechanisms that have ripened the field of "mechanical metamaterials" and "architected materials" in the last decades is explored. In particular, the important role and various implementations, both in 2D and 3D, of "rotating rigid units," which range from "rotating squares" to much more complex renditions at various scales of structure, are looked at. The role of rotating rigid units to generate negative thermal expansion and negative compressibility is also delved into. [ABSTRACT FROM AUTHOR]

On‐water rowing is a sport where participants make extensive, powerful, and complex repetitive movements with their wrists to pull and feather (twist) the oar. Herein, the aim is to assess the frequency and perceived causes of wrist and forearm pain in rowers and, in particular, assess whether there are any possible mechanical issues that could be addressed through the use of auxetic technology. Through an online survey of 145 on‐water rowers, it is found that 33.8% of the rowers reported wrist or forearm pain arising from rowing. The majority (67.3%) consider over‐gripping to be the cause while one out of five associated it with periods of tension and anxiety, which also led them to over‐grip. This indicates that rowing handles could benefit from the use of mechanical metamaterials, auxetics in particular, owing to their anomalous manner in how they deform when subjected to mechanical deformations. Moreover, given the rise in popularity of coastal rowing, which will become an Olympic discipline alongside classic rowing as from the 2028 Los Angeles Olympic Games, the potential use of auxetics in the manufacture of protective gear for use in coastal rowing is also discussed. [ABSTRACT FROM AUTHOR]

Poly(phenylacetylene) sheets that mimic the geometry of a wine-rack-like structure have been predicted to exhibit negative Poisson's ratios off-axis. However, their potential to exhibit negative linear compressibility (NLC) has remained largely unexplored. In this work, the compressibility and other mechanical properties of wine-rack-like poly(phenylacetylene) networks with 1,2,4,5 tetra-substituted phenyls as well as their equivalent with allene or cyclobutadiene centres are simulated to assess their ability to exhibit negative linear compressibility on-axis and off-axis. It is shown that some of these systems can indeed exhibit negative linear compressibility whilst others exhibit a near-zero compressibility. The results are compared to the compressibility properties of other poly(phenylacetylene) networks reported in literature as well as with those predicted from the analytical model for an idealised wine-rack structure deforming through hinging. Results suggest that these mechanical properties are arising from a wine-rack-like mechanism, and there is a good agreement with the theoretical model, especially for systems with longer acetylene chains whose geometry is closer to that of the idealised wine-rack. [ABSTRACT FROM AUTHOR]

Auxetics (negative Poisson's ratio) and materials with negative linear compressibility (NLC) exhibit the anomalous mechanical properties of getting wider rather than thinner when stretched and expanding in at least one direction under hydrostatic pressure, respectively. A novel mechanism—termed the 'triangular elongation mechanism'—leading to such anomalous behavior is presented and discussed through an analytical model. Amongst other things, it is shown that this novel mechanism, when combined with the well-known 'rotating squares' model, can generate giant negative Poisson's ratios when the system is stretched. [ABSTRACT FROM AUTHOR]