Article
Engineering, Aerospace
Yewei Zhang, Zhi Li, Kefan Xu, Jian Zang
Summary: A novel pyramid lattice sandwich structure with active variable stiffness (AVS) is proposed, which has excellent self-adjusting and active vibration reduction effect. Through analysis and comparison of the impact of different parameters, it is proven that the structure can achieve ideal vibration reduction effect.
AEROSPACE SCIENCE AND TECHNOLOGY
(2021)
Article
Mechanics
Xiujie Zhu, Chao Xiong, Junhui Yin, Zhaoshu Yang, Haitao Sun, Huiyong Deng, Kaibo Cui, Youchun Zou
Summary: The stiffness, failure load and failure mechanism of carbon fibre reinforced plastic (CFRP) composite trapezoidal corrugated sandwich plates (CTCSPs) under four-point bending load were investigated. Experimental tests, modeling predictions, and parametric analysis were conducted. The results showed that by increasing theta, the limit load of the specimens first increased and then decreased while the stiffness decreased. The failure modes observed were shear corrugation fracture, debonding, and face fracture. The study also presented the variations in stiffness parameters and failure mechanism maps.
COMPOSITE STRUCTURES
(2023)
Article
Forestry
Dongxia Yang, Changsheng Fan, Yingcheng Hu
Summary: This study investigated the mechanical properties of a fabricated 2D wooden pyramid lattice sandwich structure and found that the arrangement of unit cells significantly affects the bearing capacity, energy absorption, and failure mode of the specimen. The results provide a theoretical basis for the future design of wood-based lattice sandwich structures.
Article
Engineering, Civil
Xianxian He, Zhixin Huang, Zhaoyue Chen, Ying Li
Summary: This study investigates the response and energy absorption performance of a CFRP-lattice sandwich structure under underwater shock wave loading through numerical simulation validation and experimental analysis, revealing different failure modes and influencing factors.
THIN-WALLED STRUCTURES
(2022)
Review
Engineering, Civil
Yong Wu, Dipeng Wu, Jia Ma, Wenchao Xiao, Kailun Zheng, Minghe Chen
Summary: The physically based constitutive modeling, simulation and experimental study focused on the manufacture of a pyramid lattice Ti-6Al-4 V sandwich panel structure using the SPF/DB process. High-temperature deformation behaviors of Ti-6Al-4 V were investigated, leading to successful predictions of thinning ratios, dislocation densities, grain sizes and damage distributions. The established constitutive model facilitated FE simulations for optimizing both macro- and micro-properties of the sandwich panels.
ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING
(2021)
Article
Multidisciplinary Sciences
Haning Xiu, Harry Liu, Andrea Poli, Guangchao Wan, Kai Sun, Ellen M. Arruda, Xiaoming Mao, Zi Chen
Summary: This study utilizes concepts from quantum topological states of matter to create a Maxwell lattice metamaterial with topologically protected features. The researchers demonstrate synchronized transitions and different stiffnesses in the lattice's topological phases both theoretically and experimentally. This metamaterial not only exhibits reversible changes in its mechanical properties, but also offers a rich design space for mechanical computing architectures and reprogrammable neuromorphic metamaterials.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Mechanics
Bing Xue, Yu-Xiang Peng, Shao-Fei Ren, Nian-Nian Liu, Qi Zhang
Summary: This paper investigates the influence of panel thickness on underwater impact resistance performance of pyramid lattice structures using the SPH-FEM method. The study involves simulations, comparisons with experimental results, and analysis of deformation and energy absorption rate to verify the effectiveness of the proposed method. The results can serve as reference for ship protection structure design.
COMPOSITE STRUCTURES
(2021)
Article
Automation & Control Systems
Emily Rogers-Bradley, Seong Ho Yeon, Christian Landis, Hugh M. Herr
Summary: The biological ankle joint adjusts its stiffness to adapt to different walking conditions. However, currently used passive transtibial prostheses do not adjust device stiffness, limiting their performance. We present a quasi-passive variable stiffness ankle-foot prosthesis that can adjust stiffness and showed promising initial results in a pilot study. This prosthesis has the potential to improve walking biomechanics through its low mass design.
IEEE-ASME TRANSACTIONS ON MECHATRONICS
(2023)
Article
Biophysics
Christophe Lecomte, Anna Lara Armannsdottir, Felix Starker, Heimir Tryggvason, Kristin Briem, Sigurdur Brynjolfsson
Summary: This paper introduces a novel prosthetic foot design capable of modulating its stiffness in the sagittal plane, demonstrated through mechanical test bench and biomechanical analysis. The VSA prosthetic foot could enhance user satisfaction and assist prosthetists in fine-tuning during fittings.
JOURNAL OF BIOMECHANICS
(2021)
Article
Engineering, Civil
Yang Wei, Si Chen, Shuaifeng Tang, Donglin Peng, Kang Zhao
Summary: This paper proposes a novel method to strengthen existing timber beams by adding high-performance engineered bamboo scrimber and carbon fiber-reinforced polymer (CFRP) layers, which can effectively enhance the flexural stiffness and strength of the beams. The experimental results show that the thickness of bamboo scrimber increases the stiffness and bending strength of the beams, while the addition of CFRP layers has no noticeable effect on the strength. The reinforced beams exhibit excellent deformability and stable durable platform segments.
JOURNAL OF COMPOSITES FOR CONSTRUCTION
(2022)
Article
Materials Science, Multidisciplinary
Lihong Yang, Lei Sui, Xuyang Li, Yalun Dong, Fan Zi, Linzhi Wu
Summary: This paper investigated the dynamic responses of multi-layer gradient pyramid lattice sandwich plates subjected to blast loadings using numerical simulation method. The gradient configuration with increasing relative density of core layer from front sheet to back sheet showed the best blast resistance.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2021)
Article
Materials Science, Composites
Na Yang, Fuzhen Sun, Puqiang Zhu, Jianfeng Wang
Summary: In this study, a new type of pyramid lattice structure is designed and fabricated using the snap-fit method, by rearranging the typical pyramid lattice structure of carbon fibre reinforced polymer composites to obtain a small node distance and simplify the fabrication procedure. The compression and bending properties of the new structure are experimentally studied, and the damage distribution in the lattice structure core is obtained via finite element simulation. The influence of core truss length and layering direction on compression and bending properties is also analyzed using finite element simulation.
JOURNAL OF REINFORCED PLASTICS AND COMPOSITES
(2023)
Article
Engineering, Mechanical
Qi Wang, Xiaolong Lu, Peng Jiang, Chang Guo, Yalin Sun
Summary: This paper presents a method for developing the 3D structure of variable-stiffness actuators using variable-stiffness joints and 3D printing technology. The authors successfully achieved programmable design and manufacture of 3D variable-stiffness actuators and developed a driving actuator and a mechanical gripper based on variable-stiffness joints. Their study provides practical solutions and guidance for the development of innovative and practical actuators.
Article
Automation & Control Systems
Haili Li, Xingzhi Li, Pan Zhou, Jiantao Yao
Summary: Soft array structures have great potential in soft grasping, soft locomotion, and interface science due to their advantages of redundancy, fault-tolerance, adaptability, and reliability. However, the variable stiffness of these structures has always been a challenge. Taking inspiration from the biological tube foot and water vascular system of starfish, this study proposes a fiber-reinforced soft fluidic tube-foot array with variable stiffness. Experimental and theoretical comparisons show a mean absolute percent error of <= 9.3% for the peak stiffness model of the bioinspired tube foot. The soft tube-foot array is then applied to soft grasping and amphibious wheels, demonstrating the contribution of this work in proposing a novel soft array structure and a simple method to control the stiffness of fluid-actuated soft array structures.
IEEE-ASME TRANSACTIONS ON MECHATRONICS
(2023)
Article
Engineering, Industrial
Jingwei Zhang, Sheng Ding, Jun Yanagimoto
Summary: This study systematically investigated the bending properties of sandwich sheets with 3D printed carbon fiber reinforced plastic lattice cores, clarifying the key factors affecting structural properties. Common failure modes during bending of sandwich sheets were deeply investigated by theoretical models and experimental tests.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2022)