Guilin Wen

Hunan University · Department of Vehicle Engineering

Robots inspired by origami that offer several benefits, including being lightweight, requiring less assembly, and possessing remarkable deformability, have drawn a lot of interest. However, the existing origami-inspired robots are usually of limited functionalities and developing feature-rich robots is very challenging. Here, we report an origami-w...

Due to variable and complex work environments, nonlinearities, uncertainty and disturbances are inevitable in multi‐agent systems. Approximation‐free control can address these issues without involving approximators, such as fuzzy logic systems and neural networks. However, some issues like the singularity problem caused by the signals exceeding the...

An easily stackable multi-layer quasi-zero-stiffness (ML-QZS) meta-structure is proposed to achieve highly efficient vibration isolation performance at low frequency. First, the distributed shape optimization method is used to design the unit cel, i.e., the single-layer QZS (SL-QZS) meta-structure. Second, the stiffness feature of the unit cell is...

Introducing origami with outstanding flexibility into thin-walled tubes can enhance their energy absorption performance. This paper first proposes a cutting and folding-based design route of thin-walled origami tubes which enables geometry gradients such as uniform, tapered, hourglass-shaped, and ellipsoidal shapes. Subsequently, the finite element...

Self-assembly formation is a key research topic for realizing practical applications in swarm robotics. Due to its inherent complexity, designing high-performance self-assembly formation strategies and proposing corresponding macroscopic models remain formidable challenges and present an open research frontier. Taking inspiration from crystallizati...

Suppression of low-frequency noise suppression is of high engineering importance. However, representative solution micro-perforated panels have limitations, including narrow effective sound absorption bands at low frequencies and excessive thickness. In this study, we design a novel Archimedean spiral channel-based acoustic metasurface (ASCBAM) fou...

Autonomous vehicles (AVs) bring advantages such as comfort, safety, and eco-friendliness compared to conventional ones. The focus on comfort has become increasingly important as it plays a key role in the widespread acceptance of AVs. Passenger demand for alleviating motion sickness (MS) during travel has also driven extensive research in this area...

Origami-inspired robots with multiple advantages, such as being lightweight, requiring less assembly, and exhibiting exceptional deformability, have received substantial and sustained attention. However, the existing origami-inspired robots are usually of limited functionalities and developing feature-rich robots is very challenging. Here, we repor...

A well-controlled active suspension system has the potential to provide better ride comfort. Benefiting from its powerful feature extraction and nonlinear generalization capabilities, the deep reinforcement learning (DRL), such as deep deterministic policy gradient (DDPG), has shown great potential to make decisions adaptively and intelligently in...

Flexible grippers with superior gripping capabilities are essential for carrying objects. Herein, an origami chomper‐based flexible gripper is designed using a combination of the origami technique and a newly developed nonlinear topology optimization method. This novel origami chomper‐based flexible gripper exhibits superior gripping performance, a...

The integrated fast detection technology for electric bikes, riders, helmets, and license plates is of great significance for maintaining traffic safety. YOLOv5 is one of the most advanced single-stage object detection algorithms. However, it is difficult to deploy on embedded systems, such as unmanned aerial vehicles (UAV), with limited memory and...

Compared with traditional quasi-zero-stiffness (QZS) isolators, the QZS isolator with displacement constraints can theoretically display a lower transmissibility peak value and a wider isolation-frequency range. Nevertheless, there is no relevant experiment to prove the correctness of this theoretical result at present. In this paper, an experiment...

The optimization of the engineering system is becoming more and more significant as time progresses, and a large number of metamodel-based multi-objective optimization methods have been proposed during the past decades. For a metamodel-based multi-objective optimization method, the accuracy of the solution is greatly influenced by the prediction ac...

Aiming to attenuate low-frequency wave in pipes, a novel metamaterial pipe with attached compliant quasi-zero-stiffness (QZS) resonators is proposed. The compliant resonator with twelve compliant multi-segment curved beams is proposed firstly to achieve quasi-zero stiffness under proper pre-compression. Theoretical investigations are conducted to d...

Existing experimental studies have shown that the dynamic morphology of dielectric elastomer (DE) membranes can effectively, and reproducibly remove biofouling, but a convincing theory to quantitatively explain anti-biofouling performance is lacking. In this study, a two-dimensional (2D) contact mechanics model is developed to quantify the effect o...

This paper presents a new class of locally resonant (LR) metamaterials with quasi-zero stiffness (QZS) in three dimensions. The monolithic QZS property is achieved by optimizing the three-dimensional (3D) resonator. For the proposed 3D QZS metamaterial, the characteristics of wave propagation are investigated. A lumped-mass-spring model is develope...

In terms of highway traffic safety, the W-beam guardrail plays an essential role in absorbing impact energy, reducing occupant acceleration peaks, and redirecting the vehicle in the correct direction. In this study, a new separate W-beam guardrail named "SWG" composed of separate posts connected by bolts was invented to improve the safety performan...

In this study, a novel compact energy harvesting dynamic vibration absorber (EHDVA) with quasi-zero-stiffness (QZS) characteristics is engineered for both vibration suppression and energy harvesting under low frequency. The QZS EHDVA is composed of a negative stiffness magnetic spring (NSMS), a spiral flexure spring (SFS) and coils. Firstly, the an...

Quasi-zero-stiffness (QZS) vibration isolators are practical solutions for isolation in the low-frequency range. However, single-layer QZS isolators have a low roll-off rate of transmissibility in the frequency band of isolation, especially at high frequencies. The purpose of this study is to design a novel two-stage QZS isolator, called TSQZS isol...

Noise reduction is of critical importance in many engineering applications. One way to achieve noise reduction is using acoustic metamaterials. However, traditional acoustic metamaterials have long been criticized for the fixed and narrow frequency band in low- and medium-frequency sound attenuation. In this study, by incorporating the accordion or...

Although the flexible origami gripper can handle a wide range of objects, there is a need for significant further improvement in its gripping performance. This study develops a novel nonlinear topology optimization (NTO) method to enhance the gripping performance of an origami chomper-based flexible gripper. The proposed NTO method incorporates the...

Cellular structure has attracted extensive attention due to its lightweight, superior mechanical properties, and excellent energy absorption property. In nature, the animal bone and plant stem both are cellular structures. It is found that these natural cellular structures additionally have a hierarchical characteristic which makes them extremely s...

Triply periodic minimal surface (TPMS) sandwich panels have superior characteristics, including lightweight and extraordinary mechanical properties, so that they are widely applied in diverse industrial and engineering applications. However, their sound suppression potential is far away understood. The present study investigates P- and G-type TPMS...

The atypical Markov decision processes (MDPs) are decision-making for maximizing the immediate returns in only one state transition. Many complex dynamic problems can be regarded as the atypical MDPs, e.g., football trajectory control, approximations of the compound Poincaré maps, and parameter identification. However, existing deep reinforcement l...

The dynamic vibration absorber (DVA) can effectively suppress undesirable vibration of a host structure, and the energy harvester is also proven to be a feasible way to collect vibration energy from the host structure. However, it is almost impossible to achieve high-efficiency vibration attenuation and energy harvesting at ultra-low frequency by c...

The continuum topology optimization method can extensively improve the structural performance from the mechanical essence, which can provide designers with a variety of innovative design candidates. Due to these advantages and significant help to engineering, the continuum topology optimization method has been rapidly developed in recent years. Thi...

Uncertainty and unknown nonlinearity are often inevitable in the suspension systems, which were often solved using fuzzy logic system or neural networks. However, these methods are restricted by the structural complexity of the controller and the huge computing cost. Meanwhile, the estimation error of such approximators is affected by adopted adapt...

Designing a high-performance controller for the walking gaits of biped robots remains an open research area due to their strong nonlinearity and non-smooth responses. To overcome such challenges, a humanoid robot with a torso, i.e., a three-link biped robot involving both impact and friction, is developed firstly. Then, the twin delayed deep determ...

Porous/multi-cell structures are widely used in practical engineering due to their excellent energy absorption capacity and lightweight. In recent decades, as an important member of porous structures, lattice structure is found to have extremely excellent energy absorption capacity per unit mass. It has become a hot spot in the research of porous s...

To achieve wave attenuation at ultra-low frequencies, a novel metamaterial plate with attached compliant quasi-zero-stiffness (QZS) resonators is proposed. Firstly, the compliant resonator is designed to fulfill the QZS feature under proper pre-compression. Then, theoretical investigations are conducted to derive the dispersion relation and reveal...

A novel metamaterial beam with embedded quasi-zero-stiffness (QZS) resonator is proposed to realize wave attenuation in very low-frequency band gaps. The configuration of the QZS resonator is developed by using compliant mechanism with design optimization, and the feature of quasi-zero stiffness is achieved under proper pre-compression. Then, the d...

The design philosophy of fail-safe structures was first proposed in the aerospace industry to provide redundant load paths as back-ups when local damage happens. Most fail-safe topology optimization methods paid more attention to minimizing compliance of the worst failure case. However, the stress concentration due to local failure may lead to seco...

Uncertainty and unknown nonlinearity are often inevitable in the suspension systems, which were often solved using fuzzy logic system (FLS) or neural networks (NNs). However, these methods are restricted by the structural complexity of the controller and the huge computing cost. Meanwhile, the estimation error of such approximators is affected by a...

Although the structural vibration can be suppressed by adjusting eigenvalues outside the excitation frequency band, it becomes increasingly difficult to suppress vibration as the width of the excitation frequency band increases. Besides, for some high-precision equipment, e.g. space telescope mirror substrate and rocket motor casings, their complex...

Quasi-zero-stiffness (QZS) vibration isolators have been widely studied, because they show excellent high static and low dynamic stiffnesses and can effectively solve low-frequency and ultralow-frequency vibration. However, traditional QZS (T-QZS) vibration isolators usually adopt linear damping, owing to which achieving good isolation performance...

This paper develops a novel type of two-dimensional (2D) locally resonant (LR) metamaterials with quasi-zero-stiffness (QZS) property both in the horizontal and vertical directions. The unit cell, constructed by attaching the 2D QZS resonator onto a square frame, is periodically arranged to form the QZS metamaterial. The QZS property along two dire...

Porous structure based on triply periodic minimal surface (TPMS) has received extensive attention due to its excellent performance and lightweight. This study aimed to propose three novel types of composite TPMS-based porous structures (PI-type, PIP-type, and PN-type) inspired by the microscopic porous structure of bones and investigate their crash...

Thin-walled structures are widely used in engineering applications. In order to improve the mechanical properties of thin-walled structures, porous structures are usually filled into thin-walled tubes. However, the widely used porous structures have the disadvantages of randomness, heterogeneity and anisotropy. Recently, a novel porous structure ca...

Three-dimensional (3D) cellular structures have been widely used in many aspects, e.g., protective equipment, aerospace, vehicles and so on, due to its lightweight and excellent energy absorption characteristics. Triply periodic minimal surface (TPMS) has more uniform energy absorption and mechanical properties than foam due to its structural chara...

Huge calculation burden and difficulty in convergence are the two central conundrums of nonlinear topology optimization (NTO). To this end, a multi-resolution nonlinear topology optimization (MR-NTO) method is proposed based on the multi-resolution design strategy (MRDS) and the additive hyperelasticity technique (AHT), taking into account the geom...

Huge calculation burden and difficulty in convergence are the two central conundrums of nonlinear topology optimization (NTO). To this end, a multi-resolution nonlinear topology optimization (MR-NTO) method is proposed based on the multi-resolution design strategy and the additive hyperelasticity technique (AHT), taking into account the geometric n...

This paper aims to study the near-grazing bifurcations in a single-degree-of-freedom impact oscillator with two-side elastic constraints, and further stabilize the near-grazing dynamics using deep reinforcement learning control. Using the numerical schemes, e.g., Graphic Processing Unit computing and continuation method, detailed bifurcation analys...

This article develops a multi-resolution topology optimization (MTOP) approach based on the solid isotropic material with penalization (SIMP) method, which is effective in obtaining high-resolution designs at low computational cost. The extended finite element method (XFEM) is employed to decouple the analysis mesh, material description and nodal d...

Evolutionary node shifting is an effective approach to the shape optimization of spatial structures for excellent mechanical performance. In this paper, a novel shape optimization algorithm is proposed, which is applicable to complex gridshell structures of irregular geometries and non-uniform grids. With the objective of maximizing the structural...

Origami-based metamaterial has shown remarkable mechanical properties rarely found in natural materials, but achieving tailored multistage stiffness is still challenging. We propose a novel zigzag-base stacked-origami (ZBSO) metamaterial with tailored multistage stiffness based on crease customization and stacking strategies. A high precision finit...

A deep understanding of the dynamical behavior in the parameter-state space plays a vital role in both the optimal design and motion control of mechanical systems. By combining the GPU parallel computing technique with two determinate indicators, namely the Lyapunov exponents and Poincaré section, this paper presents a detailed study on the two-par...

Vibration isolation systems with quasi-zero stiffness (QZS) performance have been widely studied because of their characteristics: high static stiffness and low dynamic stiffness. However, the effective displacement range of QZS is usually so small that strongly limits its application existing in real engineering. Thus, this study’ main innovation...

Origami-baed metamaterial has shown remarkable mechanical properties rarely found in natural materials, but achieving tailored multistage stiffness is still a challenge. This study proposes a novel zigzag-base stacked-origami (ZBSO) metamaterial with tailored multistage stiffness property based on crease customization and stacking strategies. A hig...

TPMS (triply periodic minimal surface) sheet structure consists of a spatially continuous surface, which forms a periodic porous structure, and has outstanding mechanical performance and ultralight weight. However, there are few studies on the periodic structure as an internal reinforcement energy absorber. In this study, we mainly discuss the coll...

The disk dynamo plays an important role in studying the geodynamo and much research works have been devoted to the understanding of dynamo dynamics. This paper further investigates an extended disk dynamo system having three coupled conducting disks and incorporates the interaction-induced time delay in the dynamic governing equations. By carrying...

Understanding of dynamical behavior in the parameter-state space plays a vital role in the optimal design and motion control of mechanical governor systems. By combining the GPU parallel computing technique with two determinate indicators, namely, the Lyapunov exponents and Poincaré section, this paper presents a detailed study on the two-parameter...

Inspired by the flight mechanism of dipteran, a novel bionic-dipteran energy harvester (BDEH) was proposed to collect ultralow-frequency vibration energy. Mimicking the skeletal structure of dipteran wing, two flexible beams and two rigid links are hinged together to form a bistable mechanism. Piezoelectric patches attached onto the flexible beams...

The quasi-zero-stiffness (QZS) vibration isolation has been proved to be an effective way to isolate low-frequency vibration. However, most of the existing QZS isolators are space-consuming, which could not be employed in the space-limited circumstances. In this paper, a quite compact QZS isolator is engineered by connecting a pair of mutually repu...

In this paper, a tunable locally resonant metamaterial is proposed for low-frequency band gaps. The local resonator composed of two pairs of folded slender beams and a proof mass is designed based on the theory of compliant mechanism. The design optimization on geometric parameters is carried out to fulfil the quasi-zero-stiffness property. The loc...

Topology optimization is a pioneer design method that can provide various candidates with high mechanical properties. However, high resolution is desired for optimum structures, but it normally leads to a computationally intractable puzzle, especially for the solid isotropic material with penalization (SIMP) method. In this study, an efficient, hig...

The prediction for the internal failure of lithium-ion batteries (LIB) under external mechanical abuse load remains a challenge for safe design. This paper systematically studies the modeling approach for progressive failure simulation and short-circuit prediction. Hemispherical indentation experiments are conducted on a battery specimen containing...

System stability has been a crucial issue in design of very large floating structures. Large responses of floating structures not only deteriorate operation conditions but also seriously affect the safety, service life and maintenance cost of structures. In this paper, an idea of using hinge connection in control is proposed for stabilizing a five-...

This paper presents a computationally efficient multi-resolution topology optimization framework by establishing a novel bi-directional evolutionary structure optimization (BESO) method based on extended finite element method (XFEM). In the proposed framework, the high-resolution designs preserving the topological complexity can be obtained with lo...

Porous structure is widely used in automobile, aerospace and other industrial fields due to its lightweight and high energy absorption capacity. In this study, a novel porous structure, i.e. hierarchical three-dimensional porous (H3DP) structure inspired by the bone in nature is created based on the primitive triply periodic minimal surface sheet s...

Abrasive jetting stream generated from accelerator tank is crucial to the precision machining of industrial products during the process of strengthen jet grinding. In this article, its effectiveness prediction using normalized sparse autoencoder-adaptive neural fuzzy inference system is carried out to provide an optimal result of jetting stream. A...

Aerodynamic characteristics of tilt-rotor UAVs are usually simulated by computational fluid dynamics (CFD) only, and the fuselage/wing is fixed in simulations. It is difficult for this method to consider drastic changes of the aerodynamic forces and flowfield originating from conversion of flight modes. And during flight-mode conversions, the rapid...

Most of the current time-variant reliability analysis methods are applicable for only random variables. However, some of the uncertain parameters can only be easily modeled by interval variables in many engineering applications. The main contribution of this paper is to propose a new time-variant reliability analysis method for nonlinear limit stat...

Following the previous work on the degenerate grazing bifurcations of impact oscillators, this paper aims to explore novel two-parameter dynamics near the degenerate grazing points using GPU parallel computing technology. By using the technology, a further understanding of the near-grazing dynamics can be developed for impact oscillators. Three mai...

A new two-dimensional (2D) phononic crystal (PC) constituted by the periodic hexagonal lattices, which is inspired by the scissor-like geodesic circle of the Hoberman sphere, is proposed in this study. The band structures, transmission spectrum as well as displacement field of the proposed PC are analyzed by employing the finite element method (FEM...

Inherent time delays are often neglected in the modeling and dynamic analysis of centrifugal governor systems for the sake of simplicity, yet they can have a significant effect on the dynamic behavior of the governor systems. This paper investigates the effect of time-delay on the dynamics of a hexagonal centrifugal governor system through a compar...