This paper introduces a new method of measuring the three-dimensional drape shape of fabrics with structural light. First, we apply parallel annular structural light to form light and shade alternating contour stripes...This paper introduces a new method of measuring the three-dimensional drape shape of fabrics with structural light. First, we apply parallel annular structural light to form light and shade alternating contour stripes on the surface of fabrics. We then collect the images of contour stripes using Charge Coupled Device (CCD). Subsequently, we process the images to identify the contour stripes and edges of fabrics, and obtain the fabric contour lines of curved surfaces. Finally, we apply three-dimensional curved surface modeling method based on a network of polar coordinates, and reconstruct the three-dimensional drape shape of fabrics. Experiments show that our method is effective in testing and reconstructing three-dimensional drape shape of fabrics.展开更多
The impeller of turbo machinery is a typical nonlinear multi-oscillator system.The vibration of each module is coupling, including fluid-solid coupling of the blade.The subject of our investigation was a KDF-5 mine fa...The impeller of turbo machinery is a typical nonlinear multi-oscillator system.The vibration of each module is coupling, including fluid-solid coupling of the blade.The subject of our investigation was a KDF-5 mine fan for which we analyzed air vibration signals and axial vibration signals by using correlation dimension analysis under five variable working conditions.The results indicate that their correlation dimension curves show a uniform trend.That is to say, the characteristics of the variation signals of the integral structure are correlated and mutually embodied.It proves that it is possible to monitor the working state of a mine fan by coupling the vibration signals and air vibration signals for these are more sensitive in representing the status of the impeller system.展开更多
To improve the performance of the 2 m telescope, the optimum design is applied to the telescope assemble. Referring to the telescope assemble with the dimetric truss, a group of reasonable sizes of the telescope assem...To improve the performance of the 2 m telescope, the optimum design is applied to the telescope assemble. Referring to the telescope assemble with the dimetric truss, a group of reasonable sizes of the telescope assemble are found by optimization methods and modal analysis, which will raise the resonant frequency by 4.21 %. As a result, the telescope assemble is less likely to resonate. Besides, the dynamic response module in ANSYS is utilized to analyze the modal type, harmonic vibration response and random vibration response of the telescope assemble. By the calculation of ANSYS, finite dement analysis (FEA) method proves that the performance of the telescope assemble is mildly enhanced by means of optimum design.展开更多
Due to the unique locomotion,the head-shaking problem of biomimetic robotic fish inevitably occurs during rectilinear locomotion,which strongly hinders its practical applications.In this paper,we experimentally study ...Due to the unique locomotion,the head-shaking problem of biomimetic robotic fish inevitably occurs during rectilinear locomotion,which strongly hinders its practical applications.In this paper,we experimentally study this problem by proposing the method of coordination control between the caudal fin and anal fin.First,an untethered biomimetic robotic fish,equipped with an anal fin,a caudal fin and two pectoral fins,is developed as the experimental platform.Second,a Central Pattern Generator(CPG)-based controller is used to coordinate the motions of the anal fin and caudal fin.Third,extensive experiments are conducted to explore different combinations of the flapping frequencies,the flapping amplitudes,and the phase differences between the anal fin and caudal fin.Notably,through proper control of the anal fin,the amplitude of the yaw motion can be as small as 4.32°,which sees a 65%improvement compared to the scenario without anal fin,and a 57%improvement compared to that with a stationary anal fin.This paper provides a novel way to alleviate the head-shaking problem for biomimetic robotic fish,and first test this method on an untethered,freely swimming robotic platform,which can shed light on the development of underwater robotics.展开更多
基金National Natural Science Foundation of China (50275139) Natural Science Foundation of Zhejiang (01388-G)
文摘This paper introduces a new method of measuring the three-dimensional drape shape of fabrics with structural light. First, we apply parallel annular structural light to form light and shade alternating contour stripes on the surface of fabrics. We then collect the images of contour stripes using Charge Coupled Device (CCD). Subsequently, we process the images to identify the contour stripes and edges of fabrics, and obtain the fabric contour lines of curved surfaces. Finally, we apply three-dimensional curved surface modeling method based on a network of polar coordinates, and reconstruct the three-dimensional drape shape of fabrics. Experiments show that our method is effective in testing and reconstructing three-dimensional drape shape of fabrics.
基金Projects BK2005018 supported by the Natural Science Foundation of Jiangsu Province CX07B-061z by the Graduate Research and Innovation Plan of Jiangsu Province
文摘The impeller of turbo machinery is a typical nonlinear multi-oscillator system.The vibration of each module is coupling, including fluid-solid coupling of the blade.The subject of our investigation was a KDF-5 mine fan for which we analyzed air vibration signals and axial vibration signals by using correlation dimension analysis under five variable working conditions.The results indicate that their correlation dimension curves show a uniform trend.That is to say, the characteristics of the variation signals of the integral structure are correlated and mutually embodied.It proves that it is possible to monitor the working state of a mine fan by coupling the vibration signals and air vibration signals for these are more sensitive in representing the status of the impeller system.
基金the Ministerial Level Advanced Rearch Foundation (304030401)
文摘To improve the performance of the 2 m telescope, the optimum design is applied to the telescope assemble. Referring to the telescope assemble with the dimetric truss, a group of reasonable sizes of the telescope assemble are found by optimization methods and modal analysis, which will raise the resonant frequency by 4.21 %. As a result, the telescope assemble is less likely to resonate. Besides, the dynamic response module in ANSYS is utilized to analyze the modal type, harmonic vibration response and random vibration response of the telescope assemble. By the calculation of ANSYS, finite dement analysis (FEA) method proves that the performance of the telescope assemble is mildly enhanced by means of optimum design.
基金Supported by National Natural Science Foundations of China(61273069,61203040) Fujian Significant Technology Projectsfor Cooperation of Industries and Universities(2013H61010135,2011H6019)+1 种基金 the Important Project of Technology Plan of FujianProvince(2009H0033) the Fundamental Research Funds for the Central Universities(JB-ZR1204)
基金The paper is funded by Natural Science Foundation of Guangdong Province(#2020A1515110692)National Natural Science Foundation of China(#51905113),Guangxi Natural Science Foundation(#2021GXNSFAA220095),Shenzhen Institute of Artificial Intelligence and Robotics for Society,SIAT Innovation Program for Excellent Young Researchers,and SIAT-CUHK Joint Laboratory of Precision Engineering.
文摘Due to the unique locomotion,the head-shaking problem of biomimetic robotic fish inevitably occurs during rectilinear locomotion,which strongly hinders its practical applications.In this paper,we experimentally study this problem by proposing the method of coordination control between the caudal fin and anal fin.First,an untethered biomimetic robotic fish,equipped with an anal fin,a caudal fin and two pectoral fins,is developed as the experimental platform.Second,a Central Pattern Generator(CPG)-based controller is used to coordinate the motions of the anal fin and caudal fin.Third,extensive experiments are conducted to explore different combinations of the flapping frequencies,the flapping amplitudes,and the phase differences between the anal fin and caudal fin.Notably,through proper control of the anal fin,the amplitude of the yaw motion can be as small as 4.32°,which sees a 65%improvement compared to the scenario without anal fin,and a 57%improvement compared to that with a stationary anal fin.This paper provides a novel way to alleviate the head-shaking problem for biomimetic robotic fish,and first test this method on an untethered,freely swimming robotic platform,which can shed light on the development of underwater robotics.