Civil infrastructure is continuously subject to aging and deterioration due to multiple factors,which lead to a decline in performance and impact structural health.Accumulated damage on structures increases operationa...Civil infrastructure is continuously subject to aging and deterioration due to multiple factors,which lead to a decline in performance and impact structural health.Accumulated damage on structures increases operational costs and poses significant risks to public safety.Effective maintenance,repair,and rehabilitation strategies are needed to ensure civil infrastructure’s overall safety and reliability.Non-Destructive Evaluation(NDE)methods are utilized to assess latent damage and provide decision-makers with real-time information for mitigating hazards.Within the last decade,there has been a significant increase in the research and development of innovative NDE techniques to improve data processing and promote efficient and accurate infrastructure assessment.This paper aims to review one of those methods,namely,Infrared Thermography(IRT),and its applications in civil infrastructure.A comprehensive review is presented by investigating numerous journal articles,research papers,and technical reports describing numerous IRT applications for bridges,buildings,and general civil structures made from different materials.The capability of IRT to identify and pinpoint anomalies,typically in the early stages of degradation,has excellent potential to improve the safety and shore up the dependability of civil infrastructures while reducing expenses tied to maintenance and rehabilitation.Furthermore,the non-invasive nature of IRT is beneficial in mitigating disturbances and downtime that may occur during various inspection procedures.It is highlighted that IRT is a highly versatile and effective tool for infrastructure condition assessment.With further advancement and fine-tuning of the available techniques,it is likely that IRT will continue to gain significant popularity in maintaining and monitoring civil infrastructure.展开更多
The sensing capabilities of a soft arm are ofparamount importance to its overall performance as they allow precise control of the soft arm and enhance its interactionwith the surrounding environment. However, the actu...The sensing capabilities of a soft arm are ofparamount importance to its overall performance as they allow precise control of the soft arm and enhance its interactionwith the surrounding environment. However, the actuationand sensing of a soft arm are not typically integrated into amonolithic structure, which would impede the arm’s movement and restrict its performance and application scope. Toaddress this limitation, this study proposes an innovativemethod for the integrated design of actuator structures andsensing. The proposed method combines the art of kirigamiwith soft robotics technology. In the proposed method, sensorsare embedded in the form of kirigami structures into actuatorsusing laser cutting technology, achieving seamless integrationwith a soft arm. Compared to the traditional amanogawakirigami and fractal-cut kirigami structures, the proposedmiddle-cut kirigami (MCK) structure does not buckle duringstretching and exhibits superior tensile performance. Based onthe MCK structure, an advanced interdigitated capacitivesensor with a high degree of linearity, which can significantlyoutperform traditional kirigami sensors, is developed. Theexperimental results validate the effectiveness of the proposedsoft arm design in actual logistics sorting tasks, demonstratingthat it is capable of accurately sorting objects based on sensorsignals. In addition, the results indicate that the developedcontinuum soft arm and its embedded kirigami sensors havegreat potential in the field of logistics automation sorting.This work provides a promising solution for high-precisionclosed-loop feedback control and environmental interaction ofsoft arms.展开更多
A research about the ultrasonic phased array imaging principle from A-scan signal to B-scan image for non-destructive testing （NDT） was conducted in this paper, the ultrasonic phased array inspection imaging system ...A research about the ultrasonic phased array imaging principle from A-scan signal to B-scan image for non-destructive testing （NDT） was conducted in this paper, the ultrasonic phased array inspection imaging system used in industrial field was developed and the experiment was performed on the steel testing block by the system with 64 elements, 5 MHz phased array transducer. Experimental results show that the flaws could be accurately detected and the flaws size could be estimated from the B-scan images, and the B-scan images could clearly show the location of the flaws, but the quality of B-scan images needs to be enhanced by digital signal processing and controlling dynamic focusing for improving the image resolution.展开更多
Composite sucker rod has been extensively used due to its high strength, light weight and corrosion resistive nature. However, such composite sucker rod is diffcult for conventional non-destructive evaluation(NDE) tec...Composite sucker rod has been extensively used due to its high strength, light weight and corrosion resistive nature. However, such composite sucker rod is diffcult for conventional non-destructive evaluation(NDE) techniques to inspect because of its complex material and/or structure. It is thus useful to embark research on developing novel NDE technique to comply the inspection requirement. This work demonstrates the feasibility of using the capacitive imaging(CI) technique for the inspection of composite sucker rod. Finite element(FE) models were constructed in COMSOL to simulate the detection of defects in the glass-fiber layer and on the carbon core surface. An FE Model based inversion method is proposed to obtain the profile of the carbon core. Preliminary CI experimental results are then presented, including the detection of surface wearing defect in the glass-fiber layer, and obtaining the profile of the carbon core. A set of accelerated aging experiments were also carried out and the results indicate that the CI technique is potentially useful in evaluating the ageing status of such composite sucker rod. The CI technique described in this work shows great potential to target some challenging tasks faced in the non-destructive evaluation of composite sucker rod, including quality control, defect detection and ageing assessment.展开更多
The laser powder bed fusion(L-PBF)method of additive manufacturing(AM)is increasingly used in various industrial manufacturing fields due to its high material utilization and design freedom of parts.However,the parts ...The laser powder bed fusion(L-PBF)method of additive manufacturing(AM)is increasingly used in various industrial manufacturing fields due to its high material utilization and design freedom of parts.However,the parts produced by L-PBF usually contain such defects as crack and porosity because of the technological characteristics of L-PBF,which affect the quality of the product.Laser ultrasonic testing(LUT)is a potential technology for on-line testing of the L-PBF process.It is a non-contact and non-destructive approach based on signals from abundant waveforms with a wide frequency-band.In this study,a method of LUT for on-line inspection of L-PBF process was proposed,and a system of LUT was established approaching the actual environment of on-line detection to evaluate the method applicability for defects detection of L-PBF parts.The detection results of near-surface defects in L-PBF 316L stainless steel parts show that the crack-type defects with a sub-millimeter level within 0.5 mm depth can be identified,and accordingly,the positions and dimensions information can be acquired.The results were verified by X-ray computed tomography,which indicates that the present method exhibits great potential for on-line inspection of AM processes.展开更多
This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their us...This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their usage in different structures, there is a need to discuss the damage types in them along with different ways of inspection. This paper provides a short review of these facts in order to fill out the gap that there is in the literature. Major emphasis is placed on the damage types and their mechanisms and inspection methods, mostly focused on wave propagation based structural health monitoring (SHM).展开更多
All vessels and offshore units require regular inspections to prevent structural or functional damages. Periodical inspections are based on classification society＇s requirements and include both visual surveys and no...All vessels and offshore units require regular inspections to prevent structural or functional damages. Periodical inspections are based on classification society＇s requirements and include both visual surveys and non-destructive test interventions, to look for structural damage, pitting, corrosion, thickness measurement, usually documented by measurements or images. Different approaches of inspection can be proposed for underwater and for dry areas, using unmanned vehicles or service robots able to improve traditional inspection methods. Several excellent proposals are today available： nevertheless, reasons of costs, operation complexity and impossibility to cover all types of inspection with a unique autonomous unit limit and conditions the applicability of automatic inspection systems. The paper is the first of a series describing the main results of a wide research activity carried out at DREAMS Lab （Laboratory of Drives and Experimental Automation for Marine Systems） of the University of Genoa. The studies are oriented to the realization of a kit of low cost and unsophisticated self-moving units, devoted to support some recursive inspections in dry areas of ships and on offshore plants as bulkheads, holds, double bottoms and ducts. The paper describes the design and prototyping of a pneumatronic unit oriented to inspection and maintenance of ship holds. Conceived to realize a portable and user-friendly tool which could take part of an ＂inspection kit＂ for the use of inspectors, able to simplify and speed up the inspection visits with and automatic generation of survey reports.展开更多
CdSe quantum-dot(QD)film,as the core function layer,plays a key role in various optoelectronic devices.The thickness uniformity of QD films is one of the key factors to determine the overall photoelectric performance....CdSe quantum-dot(QD)film,as the core function layer,plays a key role in various optoelectronic devices.The thickness uniformity of QD films is one of the key factors to determine the overall photoelectric performance.Therefore,it is important to obtain the thickness distribution of large-area QD films.However,it is difficult for traditional methods to quickly get the information related to its thickness distribution without introducing additional damage.In this paper,a non-contact and non-destructive inspection method for in-situ detecting the thickness uniformity of CdSe QD film is proposed.The principle behind this in-situ inspection method is that the photoluminescence quenching phenomenon of the QD film would occur under a high electric field,and the degree of photoluminescence quenching is related to the thickness of the quantum dot films.Photoluminescence images of the same QD film without and with an electric field are recorded by a charge-coupled device camera,respectively.By transforming the brightness distribution of these two images,we can intuitively see the thickness information of the thin film array of QD.The proposed method provides a meaningful inspection for the manufacture of QD based lightemitting display.展开更多
In view of social development,the demand for water conservancy engineering applications continues to increase.The number and scale of water conservancy projects in China have been in a state of continuous expansion in...In view of social development,the demand for water conservancy engineering applications continues to increase.The number and scale of water conservancy projects in China have been in a state of continuous expansion in recent years.As a result,how to achieve efficient testing and effective control of the quality of water conservancy projects has always been a topic of discussion in the field of water conservancy engineering in our country.This paper summarizes the application of non-destructive testing technology in the quality testing and control of water conservancy projects.On the basis of explaining the connotation and application advantages of non-destructive testing technology,the non-destructive testing application strategies for concrete strength,steel corrosion and shallow cracks in water conservancy projects were studied.展开更多
The non-destructive testing(NDT)of debonding in stainless steel composites plate(SSCP)is performed by infrared thermography,finite element analysis(FEA)software ANSYS is taken as the simulative tool,and 2D simulative ...The non-destructive testing(NDT)of debonding in stainless steel composites plate(SSCP)is performed by infrared thermography,finite element analysis(FEA)software ANSYS is taken as the simulative tool,and 2D simulative model has been set up to investigate effect of the thickness of coating and/or substrate on the detectibility of debonging in SSCPs.Two parameters,namely the maximum defect temperature difference and defect appearing index,are defined to evaluate the detectivity of defects,and their computational methods and formulas are given respectively.The preliminary changing tendency of the maximum defect temperature difference and defect appearing index with the thickness of coating and/or substrate is found by numerical simulation.展开更多
文摘Civil infrastructure is continuously subject to aging and deterioration due to multiple factors,which lead to a decline in performance and impact structural health.Accumulated damage on structures increases operational costs and poses significant risks to public safety.Effective maintenance,repair,and rehabilitation strategies are needed to ensure civil infrastructure’s overall safety and reliability.Non-Destructive Evaluation(NDE)methods are utilized to assess latent damage and provide decision-makers with real-time information for mitigating hazards.Within the last decade,there has been a significant increase in the research and development of innovative NDE techniques to improve data processing and promote efficient and accurate infrastructure assessment.This paper aims to review one of those methods,namely,Infrared Thermography(IRT),and its applications in civil infrastructure.A comprehensive review is presented by investigating numerous journal articles,research papers,and technical reports describing numerous IRT applications for bridges,buildings,and general civil structures made from different materials.The capability of IRT to identify and pinpoint anomalies,typically in the early stages of degradation,has excellent potential to improve the safety and shore up the dependability of civil infrastructures while reducing expenses tied to maintenance and rehabilitation.Furthermore,the non-invasive nature of IRT is beneficial in mitigating disturbances and downtime that may occur during various inspection procedures.It is highlighted that IRT is a highly versatile and effective tool for infrastructure condition assessment.With further advancement and fine-tuning of the available techniques,it is likely that IRT will continue to gain significant popularity in maintaining and monitoring civil infrastructure.
基金supported in part by the National Science Foundation for Young Scientists of China (51705098)。
文摘The sensing capabilities of a soft arm are ofparamount importance to its overall performance as they allow precise control of the soft arm and enhance its interactionwith the surrounding environment. However, the actuationand sensing of a soft arm are not typically integrated into amonolithic structure, which would impede the arm’s movement and restrict its performance and application scope. Toaddress this limitation, this study proposes an innovativemethod for the integrated design of actuator structures andsensing. The proposed method combines the art of kirigamiwith soft robotics technology. In the proposed method, sensorsare embedded in the form of kirigami structures into actuatorsusing laser cutting technology, achieving seamless integrationwith a soft arm. Compared to the traditional amanogawakirigami and fractal-cut kirigami structures, the proposedmiddle-cut kirigami (MCK) structure does not buckle duringstretching and exhibits superior tensile performance. Based onthe MCK structure, an advanced interdigitated capacitivesensor with a high degree of linearity, which can significantlyoutperform traditional kirigami sensors, is developed. Theexperimental results validate the effectiveness of the proposedsoft arm design in actual logistics sorting tasks, demonstratingthat it is capable of accurately sorting objects based on sensorsignals. In addition, the results indicate that the developedcontinuum soft arm and its embedded kirigami sensors havegreat potential in the field of logistics automation sorting.This work provides a promising solution for high-precisionclosed-loop feedback control and environmental interaction ofsoft arms.
基金Funded by"863"of The High-Tech Research and Development Program of China (No.2003AA602230).
文摘A research about the ultrasonic phased array imaging principle from A-scan signal to B-scan image for non-destructive testing （NDT） was conducted in this paper, the ultrasonic phased array inspection imaging system used in industrial field was developed and the experiment was performed on the steel testing block by the system with 64 elements, 5 MHz phased array transducer. Experimental results show that the flaws could be accurately detected and the flaws size could be estimated from the B-scan images, and the B-scan images could clearly show the location of the flaws, but the quality of B-scan images needs to be enhanced by digital signal processing and controlling dynamic focusing for improving the image resolution.
基金Supported by National Natural Science Foundation of China(Grant Nos.51675536,51574276)Fundamental Research Funds for the Central Universities of China(Grant No.18CX02084A)Innovative Talents Program of Far East NDT New Technology&Application Forum
文摘Composite sucker rod has been extensively used due to its high strength, light weight and corrosion resistive nature. However, such composite sucker rod is diffcult for conventional non-destructive evaluation(NDE) techniques to inspect because of its complex material and/or structure. It is thus useful to embark research on developing novel NDE technique to comply the inspection requirement. This work demonstrates the feasibility of using the capacitive imaging(CI) technique for the inspection of composite sucker rod. Finite element(FE) models were constructed in COMSOL to simulate the detection of defects in the glass-fiber layer and on the carbon core surface. An FE Model based inversion method is proposed to obtain the profile of the carbon core. Preliminary CI experimental results are then presented, including the detection of surface wearing defect in the glass-fiber layer, and obtaining the profile of the carbon core. A set of accelerated aging experiments were also carried out and the results indicate that the CI technique is potentially useful in evaluating the ageing status of such composite sucker rod. The CI technique described in this work shows great potential to target some challenging tasks faced in the non-destructive evaluation of composite sucker rod, including quality control, defect detection and ageing assessment.
基金the National Key R&D Program of China(Grant No.2018YFB1106100)。
文摘The laser powder bed fusion(L-PBF)method of additive manufacturing(AM)is increasingly used in various industrial manufacturing fields due to its high material utilization and design freedom of parts.However,the parts produced by L-PBF usually contain such defects as crack and porosity because of the technological characteristics of L-PBF,which affect the quality of the product.Laser ultrasonic testing(LUT)is a potential technology for on-line testing of the L-PBF process.It is a non-contact and non-destructive approach based on signals from abundant waveforms with a wide frequency-band.In this study,a method of LUT for on-line inspection of L-PBF process was proposed,and a system of LUT was established approaching the actual environment of on-line detection to evaluate the method applicability for defects detection of L-PBF parts.The detection results of near-surface defects in L-PBF 316L stainless steel parts show that the crack-type defects with a sub-millimeter level within 0.5 mm depth can be identified,and accordingly,the positions and dimensions information can be acquired.The results were verified by X-ray computed tomography,which indicates that the present method exhibits great potential for on-line inspection of AM processes.
文摘This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their usage in different structures, there is a need to discuss the damage types in them along with different ways of inspection. This paper provides a short review of these facts in order to fill out the gap that there is in the literature. Major emphasis is placed on the damage types and their mechanisms and inspection methods, mostly focused on wave propagation based structural health monitoring (SHM).
文摘All vessels and offshore units require regular inspections to prevent structural or functional damages. Periodical inspections are based on classification society＇s requirements and include both visual surveys and non-destructive test interventions, to look for structural damage, pitting, corrosion, thickness measurement, usually documented by measurements or images. Different approaches of inspection can be proposed for underwater and for dry areas, using unmanned vehicles or service robots able to improve traditional inspection methods. Several excellent proposals are today available： nevertheless, reasons of costs, operation complexity and impossibility to cover all types of inspection with a unique autonomous unit limit and conditions the applicability of automatic inspection systems. The paper is the first of a series describing the main results of a wide research activity carried out at DREAMS Lab （Laboratory of Drives and Experimental Automation for Marine Systems） of the University of Genoa. The studies are oriented to the realization of a kit of low cost and unsophisticated self-moving units, devoted to support some recursive inspections in dry areas of ships and on offshore plants as bulkheads, holds, double bottoms and ducts. The paper describes the design and prototyping of a pneumatronic unit oriented to inspection and maintenance of ship holds. Conceived to realize a portable and user-friendly tool which could take part of an ＂inspection kit＂ for the use of inspectors, able to simplify and speed up the inspection visits with and automatic generation of survey reports.
基金financially supported by the National Key Research and Development Program of China(2021YFB3600400)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Project(2020ZZ113 and 2021ZZ130)。
文摘CdSe quantum-dot(QD)film,as the core function layer,plays a key role in various optoelectronic devices.The thickness uniformity of QD films is one of the key factors to determine the overall photoelectric performance.Therefore,it is important to obtain the thickness distribution of large-area QD films.However,it is difficult for traditional methods to quickly get the information related to its thickness distribution without introducing additional damage.In this paper,a non-contact and non-destructive inspection method for in-situ detecting the thickness uniformity of CdSe QD film is proposed.The principle behind this in-situ inspection method is that the photoluminescence quenching phenomenon of the QD film would occur under a high electric field,and the degree of photoluminescence quenching is related to the thickness of the quantum dot films.Photoluminescence images of the same QD film without and with an electric field are recorded by a charge-coupled device camera,respectively.By transforming the brightness distribution of these two images,we can intuitively see the thickness information of the thin film array of QD.The proposed method provides a meaningful inspection for the manufacture of QD based lightemitting display.
文摘In view of social development,the demand for water conservancy engineering applications continues to increase.The number and scale of water conservancy projects in China have been in a state of continuous expansion in recent years.As a result,how to achieve efficient testing and effective control of the quality of water conservancy projects has always been a topic of discussion in the field of water conservancy engineering in our country.This paper summarizes the application of non-destructive testing technology in the quality testing and control of water conservancy projects.On the basis of explaining the connotation and application advantages of non-destructive testing technology,the non-destructive testing application strategies for concrete strength,steel corrosion and shallow cracks in water conservancy projects were studied.
基金the National Natural Science Foundation of China(No.51075388)the Fundamental Research Funds for the Central Universities (No.2009KJ05)
文摘The non-destructive testing(NDT)of debonding in stainless steel composites plate(SSCP)is performed by infrared thermography,finite element analysis(FEA)software ANSYS is taken as the simulative tool,and 2D simulative model has been set up to investigate effect of the thickness of coating and/or substrate on the detectibility of debonging in SSCPs.Two parameters,namely the maximum defect temperature difference and defect appearing index,are defined to evaluate the detectivity of defects,and their computational methods and formulas are given respectively.The preliminary changing tendency of the maximum defect temperature difference and defect appearing index with the thickness of coating and/or substrate is found by numerical simulation.
