Xiaoying Cheng
@zstu.edu.cn
Zhejiang Sci-Tech University
Scopus Publications
Scopus Publications
Zhenyu Wu, Feihong Chen, Zhongxiang Pan, Zhanjun Wu, Xiaoying Cheng, and Kehong Zheng
Springer Science and Business Media LLC
Zhenyu Wu, Panyou Zhang, Shuang Qin, Xiaoying Cheng, and Kehong Zheng
Elsevier BV
Xiaoying Cheng, Xuyang Cao, Zhenyu Wu, Zhiping Ying, Duncan Camilleri, and Xudong Hu
Wiley
Zhenyu Wu, Kang Wang, Lin Shi, Xiaoying Cheng, and Yanhong Yuan
Wiley
Xiaoying Cheng, Gaoshen Ma, Zhenyu Wu, Hongfei Zu, and Xudong Hu
Elsevier BV
Xiaoying Cheng, Jinghua Ying, Zhenyu Wu, Lin Shi, and Xudong Hu
Elsevier BV
Xiaoying Cheng, Ping Chen, Zhenyu Wu, Martin Cech, Zhiping Ying, and Xudong Hu
Institute of Electrical and Electronics Engineers (IEEE)
Thermography is widely used to detect delamination defects in carbon fiber-reinforced plastics (CFRPs). This article proposes a model to detect defects automatically by extracting the thermal signal characteristics of CFRP materials. An optically excited thermography system is constructed for pulsed and lock-in thermography (LT) experiments to compare thermal signal datasets in different excitation modes. A multi-task joint loss function is defined to train the model for defect detection and depth prediction. The effects of different attention modules (AMs) are analyzed to improve the model performance. By comparing the effects of traditional thermography processing methods and methods based on convolutional neural network (CNN), it is found that the proposed model can detect defects with a minimum aspect ratio (ratio of short side to depth) of 2.5, and a relative error percentage in-depth prediction is below 10%.
Zhongxiang Pan, Mingling Wang, Zhiping Ying, Xiaoying Cheng, and Zhenyu Wu
SAGE Publications
Failure mechanism of complex profile component is always different from that of conventional plate counterpart due to the coupling effect of material and structure. In this work, the low-velocity impact (LVI) and compression after impact (CAI) behaviors of Ω-shape hybrid carbon/Kevlar 3 D orthogonal woven (3DOW) composite made for vehicle B-pillar were comprehensively studied by mechanical tests and mesoscale finite element (FE) analysis at component level, high-speed infrared (IR) thermal imaging, acoustic emission (AE) detection, and microscopic damage morphology characterization. It is found that a through-thickness stress concentration ring leads to high stress state and damage zone penetrating from the impact side to non-impact side along the ring path instead of at the lowest impactor position. The slope effect can not only help the stress conduction downward, but also inhibit the damage propagation from the impact side to the slope. Impact-induced cracks are concentrated around the R corners and extended along the axial direction of the specimen, forming the strip-shaped damage concentration zone along the upper eave of the slope. The Progressive Top-Down Crushing (PTDC) mode of compression after impact is due to the complex deformation process of each yarn such as squeezing, folding and eversion in the crushing process from the top of specimen. And the Middle Indentation Fracture (MIF) mode is the result of bending instability and abrupt fracture. This work presents a reference significance for the further development of composite strengthening components in vehicle bodywork.
Lin Shi, Zhenyu Wu, Xiaoying Cheng, Zhongxiang Pan, and Yanhong Yuan
SAGE Publications
Thanks to the 2D braiding manufacturing method, the hybrid braided composite composed of the biaxial and unidirectional layers is available in a mass-production manner. For enhancing the crashworthiness of braided composite tubes, the damage characteristics and energy absorption capacity of braided composite with biaxial/unidirectional hybridization structures under axial compression were studied in this work. The axial compression tests were conducted on pure biaxial and unidirectional braided tubes (BBB and UUU), and hybrid tubes with different surface and inner layers (BUB and UBU). Micro-CT was utilized to analyze the crack characteristic and propagation inside the tubes. It was found that the easily progressed intra-laminar cracks in unidirectional layers promoted splitting damage feature, leading to enhanced energy absorption capacities in hybrid tubes than pure biaxial braided tube, in which local buckling damage feature was observed attributed to interlaced yarns induced constrained intra-laminar crack propagation and tendency to delamination. In particular, the UBU tube dissipated 20.4% more crushing energy and exhibited 13.0% higher energy absorption per unit area than the BBB tube.
Yisheng Liu, Xinlei Zhou, Xiaoying Cheng, and Dandan Liu
SAGE Publications
In this paper, numerical simulation and laboratory experiments were combined to research the tucked-in behavior of the yarn in the pneumatic tucked-in selvedge apparatus, and explore the effect of initial pressure of oblique-blowing airflow and folding-in airflow on yarn tucked-in. This work focused on the motion of a single yarn of which one end was fixed while the other was free. Initial pressures for oblique-blowing airflow and folding-in airflow were set as parameters. A numerical model was developed to simulate the process based on the one-way fluid–structure interaction. Then a laboratory experiment was carried out with the help of a high-speed camera to record the motion behaviors of yarns. The motions were compared with the simulation data and showed that the proposed numerical model can properly replicate the motion of yarn and its points in the airflow field. Each group of yarns with different initial pressures was able to be tucked-in and had an elongation. Increasing the initial pressures of oblique-blowing airflow from 0.3 MPa to 0.4 MPa and folding-in airflow from 0.35 MPa to 0.4MPa shortened the time for the yarn to complete the entire oblique-blowing and tucked-in process by 0.4625 ms, and extended the yarn elongation by 0.151 mm.
Yi Gong, Xiaoying Cheng, Zhenyu Wu, Yisheng Liu, Ping Yu, and Xudong Hu
Institute of Electrical and Electronics Engineers (IEEE)
This paper proposes a novel flexible tactile sensor array for dynamic triaxial force measurement. Piezoresistive nanofibers, which are fabricated via the electrospinning method and are composed of multi-wall carbon nanotubes (MWCNTs) and thermoplastic polyurethane (TPU), are selected as the sensing material. The sensitive piezoresistive layer, which has micron-scale thickness, is wrapped in polydimethylsiloxane (PDMS) with a bumped surface. This structure not only detects triaxial forces of different magnitudes and frequencies, but also can recognize the shape, size, and curvature of external objects using multiple measuring points of the sensor. When the sensor is subjected to normal forces at different frequencies, the measuring voltage shows good responses with variations of less than 1.21 %. When the sensor is subjected to shear forces, the coefficient of variation is less than 2.05%. In addition, when the sensor is stressed at multiple measuring points, the voltage response errors between the different points are less than 5.29%. The sensor shows high sensitivity (with a resistance change that can reach four orders of magnitude) and high response-speeds (response within 62 ms) in validation experiments. The proposed flexible sensor is efficient in triaxial force detection and has the potential for application to prosthetic hands and wearable devices.
Lin Shi, Zhenyu Wu, Xiaoying Cheng, Zhongxiang Pan, and Yanhong Yuan
Elsevier BV
Lin Shi, Zhenyu Wu, Xiaoying Cheng, Xin Ru, and Yanhong Yuan
Elsevier BV
Zhenyu Wu, Chengjian Wu, Yisheng Liu, Xiaoying Cheng, and Xudong Hu
Elsevier BV
Zhenyu Wu, Lin Shi, Xiaoying Cheng, Zhong Xiang, and Xudong Hu
Elsevier BV
Xiaoying Cheng, Yi Gong, Yisheng Liu, Zhenyu Wu, and Xudong Hu
IOP Publishing
This paper presents a novel flexible tactile sensor for triaxial force dynamic measurement based on piezoelectric elastomer. The piezoelectric elastomer is flexible composite of polyvinylidene fluoride (PVDF) terpolymer and polydimethylsiloxane (PDMS), and multi-wall carbon nanotubes (MWCNTs) are added into the elastomer to improve the piezoelectricity. The elastomer is placed under a PDMS bump and divided into four sensing units by attaching separated copper electrodes. Electrical charges generated by the sensing units are corresponding to the triaxial contact force and the amplitudes of the component forces in three directions could be obtained via the charge outputs of the proposed sensor. Prototype sensors were validated through dynamic tests and the results showed that the sensitivity of the sensor could be improved by adjusting the content of PVDF (10% to 30%) and MWCNTs (0% to 4%). Specifically, the sensitivity in normal direction would increase by 85% as the content of PVDF increases and increase by over 150% as the content of the MWCNTs increases. Accordingly, the sensitivity in shear direction would increase by 45% and 85%, respectively.
Xiaoying Cheng, Yi Gong, Yisheng Liu, Zhenyu Wu, and Xudong Hu
Elsevier BV
Xudong Hu, Zhiping Ying, Xiaoying Cheng, and Zhenyu Wu
SAGE Publications
The main goal of this study was to investigate the effect of tow tension and related internal micro-structure on the damage behavior of 3D orthogonal woven composites under tensile loading. For representing the internal micro-structure of the composite with respect to varying tow cross-section and the unregulated undulated path which are introduced by Z-binder tension, a dynamical method at filament level which simulates an interlacing process was used to obtain the fabric architecture. Then, an element recognition algorithm was proposed to convert a representative unit cell of 3D woven fabric architectures into a finite element model with 8-node solid elements consisting of four kinds of sets in terms of warp, weft, Z-binder tows and resin matrix. In addition, filament trajectory was also extracted from fabric architecture to serve as a local material orientation. Comparative simulations under tensile loading were conducted on the FEA models generated by this work and texgen software, respectively. An experiment was also carried out to verify the simulation results. The stress–strain curve in the proposed model was found to be closer to the experiment data. The results show that the tensile modulus and strength reduce due to the diverged warp tow path which is induced by the interaction between the tows during the weaving process. Moreover, the irregularity and compressed weft tow cross-sections nearby the intercross point are more likely to generate the transverse damage which would result in the non-linear tensile behavior of the composite material.
Zhiping Ying, Xudong Hu, Xiaoying Cheng, and Zhenyu Wu
SAGE Publications
The fabric geometry determines the mechanical performance of a textile composite. This paper investigates the effect of tow tension on the fabric geometry during the weaving process. A numerical model at the fiber scale was established by representing the fiber as a chain of truss elements connected by fully flexible hinges and having strong tensile modules. Fabric samples were woven on a homemade loom under different tension configurations to verify the numerical model. The model results with respect to the tow cross-section and path are in good agreement with observations of the homemade fabric sample. The tow cross-section deformation is the consequence of fiber rearrangement due to the transverse force originating from Z-binder tension. It is also found that the crimps of weft tows are different to those of warp tows. For weft tows, appreciable crimping is found in the regions of intercrossing with the Z-binder tow. Meanwhile, fibers undulate at the edges and remain straight in the middle of warp tows.
Zhenyu Wu, Maolin Wang, Zhiping Ying, Xiaoying Cheng, and Xudong Hu
SAGE Publications
This paper reports the mechanical response of semi-hexagonal part with three different multi-layer reinforcements. Unidirectional, plain woven and orthogonal fabric under quasi-static axial compression were considered. Meso-scale finite element numerical models with failure criterion were also established to simulate the onset and development of internal damage during the compression process. There were two different crush-failure modes occurring in the crush tests of the three different composite samples: a splaying mode for samples with unidirectional fabric, a buckling mode for samples with 3D orthogonal woven fabric and a mixture mode of both buckling and splaying for samples with the plain woven fabric. The samples reinforced by unidirectional fiber have the highest specific energy absorption and lowest peak loading, whereas the samples by 3D orthogonal fabric present the lowest specific energy absorption and highest peak loading. It was also demonstrated by a numerical model that the existence of Z-binder suppresses the delamination by restraining the expanding of warp and weft yarns. The comparison of numerical results and experimental data indicates that the structure of reinforcement has a significant role in the mechanical performance of textile composite.
Zhenyu Wu, Lin Shi, Xiaoying Cheng, Yisheng Liu, and Xudong Hu
Springer Science and Business Media LLC
Xiaoying Cheng, Hongshui Zhou, Zhenyu Wu, and Xudong Hu
SAGE Publications
In this paper, electrical resistance measurement (ERM) was used to detect the direction and amplitude of the bending force on fiber-reinforced polymer composite (FRPC) tubes. The method was based on research into the influence of position on the sensing behaviors of carbon fibers (CFs) as separated resistive elements under flexural tests. CFs were inserted into the fabric reinforcement fabricated by a circular braiding machine as axial tows that are separated by bias tows (Kevlar fibers) to serve as sensors. In experiments, samples of FRPC tubes with four axial tows were fabricated and bent at two different angles relative to the distribution of CFs while deformation was maintained in the elastic zone. The resistance change ratios of the CFs varies from −1.5% to 0.3% and the zero-crossing point on the tube is at 105°. The results showed that CF resistances would change in a particular pattern as the tube was being bent, and the bending direction and force amplitude could be derived from this pattern.
Xiaoying Cheng, Hongshui Zhou, Zhenyu Wu, and Xudong Hu
SAGE Publications
In this paper, the influence of damage and deformation on the electrical property of carbon fibers in the hat-shaped 3D orthogonal woven fabric-reinforced composite structure is studied. A method of producing parallel sensor arrays was proposed, in which the warp yarns made of carbon fibers were separated by isolated Kevlar fibers as weft yarns and Z-yarns. The sensor array unitized the self-sensing property of carbon fiber and could detect the damage and deformation distribution along the transverse direction of the composite under bending tests. Both the experiments and simulations had been conducted to analyze the mechanical and electrical responses of the carbon fiber array. By comparing the experimental results and simulation data, the method was validated and the influences of damage and deformation distribution on the resistance variation of carbon fibers were revealed.
Weiting Liu, Xiaoying Cheng, Xiaodong Ruan, and Xin Fu
MDPI AG
This present paper describes a novel method to fabricate tactile sensor arrays by producing aligned multi-walled carbon nanotubes (MWNTs)-polyurethane (PU) composite sub-microfiber (SMF) arrays with the electrospinning technique. The proposed sensor was designed to be used as the artificial skin for a tactile sensation system. Although thin fibers in micro- and nanoscale have many good mechanical characteristics and could enhance the alignment of MWNTs inside, the high impedance as a consequence of a small section handicaps its application. In this paper, unidirectional composite SMFs were fabricated orthogonally to the parallel electrodes through a low-cost method to serve as sensitive elements (SEs), and the impedances of SEs were measured to investigate the changes with deformation caused by applied force. The particular piezoresistive mechanism of MWNTs disturbed in SMF was analyzed. The static and dynamic test results of the fabricated tactile sensor were also presented to validate the performance of the proposed design.
Weiting Liu, Ping Yu, Chunxin Gu, Xiaoying Cheng, and Xin Fu
Institute of Electrical and Electronics Engineers (IEEE)
Roughness is a primary perceptual dimension of surface texture and plays an important role in human and robotic tactile object perception. In human, the magnitude estimates of roughness are independent of scanning velocity. On the other hand, artificial roughness encoding had to work under known scanning velocity or carry out stereotyped exploratory movement with almost the same velocity in each step action. We here presented a new fingertip piezoelectric tactile sensor array with a density similar to human Pacinian Corpuscles and capable of roughness eliciting from exploration. A novel characteristic variable <inline-formula> <tex-math notation="LaTeX">$\\Delta tf_{\\mathrm {prin.}}$ </tex-math></inline-formula>, which is product of response time interval between adjacent sensor units and the principal frequency of vibration, is first time proposed for roughness recognition. And the new characteristic variable is sensitive to surface roughness but independent of the scanning velocity. With the proposed characteristic variable, seven stimuli with a spatial period of 300, 400, 440, 480, 600, 800, and <inline-formula> <tex-math notation="LaTeX">$1000~\\mu \\text{m}$ </tex-math></inline-formula> were successfully distinguished under varying scanning velocity exploration, with an identification accuracy of 99.93%. Above used velocity range is from 10 to 150 mm/s, which can fully cover velocities in common application neurophysiologic studies and human natural exploration. Repeatability is comparatively good with average relative standard deviation of only 1.31%. Furthermore, experiments with elliptical grating verified that this roughness encoding method also fits for the texture with two-dimensional pattern. In addition, texture amplitude detection experiments were performed and results show that the vibration amplitude (<inline-formula> <tex-math notation="LaTeX">$\\text{A}_{prin.}$ </tex-math></inline-formula>) grows linearly when the texture amplitude (<inline-formula> <tex-math notation="LaTeX">$h$ </tex-math></inline-formula>) changes from 25 to <inline-formula> <tex-math notation="LaTeX">$300~\\mu \\text{m}$ </tex-math></inline-formula>.