A bolt loosening detection method based on patch antenna with overlapping sub-patch

2021 ◽  
pp. 147592172110556
Author(s):  
Songtao Xue ◽  
Xianzhi Li ◽  
Liyu Xie ◽  
Zhuoran Yi ◽  
Guochun Wan
Keyword(s):  
Finite Element Analysis ◽  
Resonant Frequency ◽  
Patch Antenna ◽  
Detection Method ◽  
Strain Sensor ◽  
Experimental Tests ◽  
Network Analyzer ◽  
Element Analysis ◽  
Electromagnetic Simulations ◽  
Bolt Loosening

Bolts are widely used in civil engineering, and the detection of bolt loosening is of great significance to ensure the safety of a structure. This paper introduces a new method for detecting bolt loosening using a customized detachable strain sensor based on a patch antenna. A patch antenna with overlapping sub-patch is proposed to measure the longitudinal elongation of the entire bolt shaft, indicating the loosening state of the bolt. When the bolt is fastened, the elongation of the bolt under tension will change the combined length of the underlying patch and the radiation sub-patch, consequently increasing or decreasing the resonant frequency of the antenna. The resonant frequency of the antenna can be measured by the vector network analyzer. Furthermore, with wireless interrogation of the strain sensor based on the patch antenna, the proposed method can also be used in the wireless detection of bolt loosening. The authors conducted a finite element analysis of the bolt and the electromagnetic simulations of the antenna. They designed the detection sensor and conducted a series of experimental tests to demonstrate how a bolt under different applied preloads can be effective and feasible under the proposed method.

scholarly journals Development of a hybrid vibration converter for real vibration source / Entwicklung eines Hybrid-Vibrationswandlers für eine echte Schwingungsquelle

2019 ◽  
Vol 86 (s1) ◽  
pp. 57-61 ◽  
Author(s):  
Sonia Bradai ◽  
Slim Naifar ◽  
Olfa Kanoun
Keyword(s):  
Magnetic Field ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Energy Harvesting ◽  
Resonant Frequency ◽  
Ambient Vibration ◽  
Vibration Source ◽  
Frequency Bandwidth ◽  
Element Analysis ◽  
The Magnetic Field

AbstractHarvesting energy from ambient vibration sources is challenging due to its low characteristic amplitude and frequencies. In this purpose, this work presents a compact hybrid vibration converter based on electromagnetic and magnetoelectric principles working for a frequency bandwidth and under real vibration source properties. The combination of especially these two principles is mainly due to the fact that both converters can use the same changes of the magnetic field for energy harvesting. The converter was investigated using finite element analysis and validated experimentally. Results have shown that a frequency bandwidth up to 12 Hz with a characteristic resonant frequency at 24 Hz and a power density of 0.11mW/cm3 can be reached.

scholarly journals Torsional Behaviour and Finite Element Analysis of the Hybrid Laminated Composite Shafts: Comparison of VARTM with Vacuum Bagging Manufacturing Method

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Mehmet Emin Taşdelen ◽  
Mehmet Halidun Keleştemur ◽  
Ercan Şevkat
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Glass Fibers ◽  
Laminated Composite ◽  
Experimental Tests ◽  
Element Model ◽  
Performance Criteria ◽  
Fiber Types ◽  
Element Analysis ◽  
Manufacturing Method

Braided sleeve composite shafts are produced and their torsional behavior is investigated. The braided sleeves are slid over an Al tube to create very strong and rigid tubular form shafts and they are in the form of 2/2 twill biaxial fiber fabric that has been woven into a continuous sleeve. Carbon and glass fibers braided sleeves are used for the fabrication of the composite shafts. VARTM (vacuum assisted resin transfer molding) and Vacuum Bagging are the two different types of manufacturing methods used in the study. Torsional behaviors of the shafts are investigated experimentally in terms of fabrication methods and various composite materials parameters such as fiber types, layer thickness, and ply angles. Comparing the two methods in terms of the torque forces and strain angles, the shafts producing entirely carbon fiber show the highest torque capacities; however, considering the cost and performance criteria, the hybrid shaft made up of carbon and glass fibers is the optimum solution for average demanded properties. Additionally, FE (finite element) model of the shafts was created and analyzed by using ANSYS workbench environment. Results of finite element analysis are compared with the values of twisting angle and torque obtained by experimental tests.

Finite element analysis of ring strain sensor

2007 ◽  
Vol 139 (1-2) ◽  
pp. 66-69 ◽  
Author(s):  
B. Chen ◽  
X. Wu ◽  
X. Peng
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Strain Sensor ◽  
Element Analysis ◽  
Ring Strain

scholarly journals Stiffness Analysis of Rectangular Isolators Reinforced by Engineering Plastics

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Han Liu ◽  
Ping Tan ◽  
Fulin Zhou
Keyword(s):  
Finite Element Analysis ◽  
Experimental Tests ◽  
Cost Effective ◽  
Seismic Protection ◽  
Fiber Reinforced ◽  
Poisson Effect ◽  
Element Analysis ◽  
Stiffness Analysis ◽  
Engineering Plastics ◽  
Improve Calculation

A novel cost-effective isolator reinforced by engineering plastics has been designed and manufactured for seismic protection for low-rise buildings in less developed areas. The reinforcement is flexible in tension, which is similar to fiber-reinforced isolators. However, available solutions for fiber-reinforced isolators are not applicable, because the Poisson effect of engineering plastics cannot be neglected, which is done for fiber reinforcement. In this paper, analytical solutions for compression and bending stiffness for rectangular isolators reinforced by engineering plastics are proposed, with both the Poisson effect of the reinforcement and the effect of rubber compressibility taken into consideration. Then, the simplified solutions are also derived, which can greatly improve calculation efficiency. To validate the solutions, finite element analysis is conducted on a set of isolators with different reinforcement stiffnesses. The results show the superiority of the proposed solutions to the previous solutions for fiber-reinforced isolators. A series of experimental tests of the isolators are also carried out to verify the solutions. Both the analytical and the simplified solutions match well with the experimental results.

scholarly journals Two-Phase Linear Hybrid Reluctance Actuator with Low Detent Force

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5162
Author(s):  
Jordi Garcia-Amorós ◽  
Marc Marín-Genescà ◽  
Pere Andrada ◽  
Eusebi Martínez-Piera
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Permanent Magnets ◽  
Thrust Force ◽  
Experimental Tests ◽  
Force Density ◽  
Two Phase ◽  
Element Analysis ◽  
Switched Reluctance ◽  
Detent Force

In this paper, a novel two-phase linear hybrid reluctance actuator with the double-sided segmented stator, made of laminated U cores, and an interior mover with permanent magnets is proposed. The permanent magnets are disposed of in a way that increases the thrust force of a double-sided linear switched reluctance actuator of the same size. To achieve this objective, each phase of the actuator is powered by a single H-bridge inverter. To reduce the detent force, the upper and the lower stator were shifted. Finite element analysis was used to demonstrate that the proposed actuator has a high force density with low detent force. In addition, a comparative study between the proposed linear hybrid reluctance actuator, linear switched reluctance, and linear permanent magnet actuators of the same size was performed. Finally, experimental tests carried out in a prototype confirmed the goals of the proposed actuator.

scholarly journals Dynamic Response of a Laminated Plate With Friction Damping

1985 ◽  
Vol 107 (4) ◽  
pp. 375-377 ◽  
Author(s):  
Shen Zhong Han
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Resonant Frequency ◽  
Laminated Plates ◽  
Laminated Plate ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Solid Plate ◽  
Sandwich Type ◽  
The Difference

A sandwich-type plate with metal facings and felt core, fastened by bolts, was studied using both test and finite-element analysis. This type of plate is cheap, light, damping-effective and without pollution; therefore, it is widely used in astronautical engineering. The tests were conducted for different felt thicknesses, bolt numbers, and fastening forces. The results show that the damping depends on friction between the plates and the felt. As compared with an identical stiffness solid plate, the damping of laminated plates can be increased up to 30 times. A mesh with rectangular elements was adopted in the finite-element analysis. In accordance with the slipping mechanism, a rectangular plate clamped on one edge was analyzed with the foregoing elements to determine the resonant frequency and the damping. The difference between the calculated and tested results was within 5 percent for the resonant frequency.

Nonlinear Finite Element Analysis of a Threaded Pipe Connection

2004 ◽  
Author(s):  
Farzad Tasbihgoo ◽  
John P. Caffrey ◽  
Sami F. Masri
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Experimental Tests ◽  
Element Model ◽  
Nonlinear Finite Element ◽  
Mitigation Measures ◽  
Element Analysis ◽  
Nonstructural Components ◽  
Small Water ◽  
Threaded Connections

For the past several years, USC has been involved in a major research project to study the seismic mitigation measures of nonstructural components in hospitals funded by the Federal Emergency Management Agency (FEMA). It was determined that piping was the one of the most critical components affecting the functionality of a hospital following an earthquake. Consequently, a substantial effort was spent on quantifying the behavior of typical piping components. During the loading of the threaded joint, it was common to hear a loud popping sound, followed by a small water leak. It was assumed that the sound and leakage were due to the sliding of the mating pipe threads. To confirm this theory, and to provide a tool to help understand the failure mode(s) for a wide class of threaded fittings, a detailed nonlinear finite element model was constructed using MSC/NASTRAN, and correlated to the measured failures. In this paper, a simplified model is presented first to demonstrate the modeling procedure and to help understand the sliding phenomenon. Next, a symmetric half 3D model was generated for modeling the physical experiments. It is shown that the finite element analysis (FEA) of the threaded connections captures the dominant mechanism that was observed in the experimental tests.

Influence of the bolt size on the source of damping in automotive joints

2021 ◽  
Vol 263 (3) ◽  
pp. 3424-3435
Author(s):  
Shaan Sanjeev ◽  
Dan J. O'Boy ◽  
Paul Cunningham ◽  
Steve Fisher
Keyword(s):  
Finite Element Analysis ◽  
Experimental Investigation ◽  
Experimental Tests ◽  
Lap Joints ◽  
Bolted Joints ◽  
Controlled Experiments ◽  
Element Analysis ◽  
Free Boundary Conditions ◽  
Single Lap Joints ◽  
Forced Excitation

Experimental tests are carried out on automotive bolted joints to study the influence of the bolt size on the source of damping during dynamic loading. Aluminium beams and five different bolt sizes are chosen and used to assemble single-lap joints under strictly controlled experiments. Measurements are taken to estimate the energy loss during forced excitation and to identify the source of damping in jointed structures, and an analogous monolithic solid beam is also used during the experimental investigation to isolate the joint effects and compare the data gathered. The dynamic response of the jointed structure exposed to forced excitation is captured under free-free boundary conditions. The motion of the assembled structure is identified by carrying out a finite element analysis.

Sign in / Sign up

Export Citation Format

Share Document