Papers by Keyword: Strain Gage

Paper TitlePage

Authors: Miroslav Pástor, Martin Hagara
Abstract: In this contribution a comparison of the results of deformation analysis performed in a classical way using strain gage and modern way, when a non-contact digital image correlation method was used, is described. Both methods were applied simultaneously for the investigation of the aluminum sample with stress concentrators loaded by tension, what prevented the investigation by different conditions. The contribution includes also the comparison of the results obtained using digital image correlation method by different levels of smoothing filters, which the software delivered together with correlation system contents.
Authors: Hung Hui Li, Wei Jen Lin
Abstract: In this study, the strains of artificial rock were analyzed in order to estimate the deformation behavior of rock-like materials in the SHPB test. The axial strain measured directly from the strain gage and obtained from the process analysis of three-wave method were compared. The analysis results show that: (1) the measurements of dynamic strains of material obtained from the strain gage method are feasible; (2) the axial strains and strain rates analyzed from the strain gage records are less than those obtained from the three-wave method; (3) the dynamic/static deformation modulus ratio Ed/Es has the increasing tendency with the raising of stress rate, and the modulus ratio obtained from the strain gage method is more than that obtained from the three-wave method.
Authors: Feng Ye, Zhong Ming Wang
Abstract: A pressure sensor used in the Common Rail System is designed to monitor the oil pressure changing form 0 to 200MPa in the temperature from -40 to 130°C. It is composed of elastic cell, strain gage and signal processing circuit. Elastic cell produces liner strain with the oil pressure; strain gage transforms this strain into electrical signal that is enlarged and processed by signal processing circuit. To describe the relation of oil pressure with the strain, the stress distribution and strain of elastic cell with different shape is simulated, applying ANSYS tool in the 200MPa pressure. Then, an acceptable shape is produced and tested. It has the similar features with simulated result and works well.
Authors: Pavel Houška, Tomáš Březina
Abstract: The article deals with description of design of sensor system for linear actuators. These constitute a part of a parallel kinematic machine based on a structure of a Stewart platform. The machine is intended for testing of bone implants in biomechanical and medical practice. The developed Stewart platform presents a mechatronic system. Hence the design of mechatronic systems known as a V-model was used. The system of sensors has been developed since the middle phase of the Stewart platform development.
Authors: Young Ho Lee, Hyung Kyu Kim
Abstract: New system (load cell) for measuring a contacting force in a high temperature and pressure water condition (i.e. 320, 15 MPa) has been developed. The primary purpose is to apply it to the experiments of a nuclear fuel fretting wear, which occurs on the contacts between the fuel rods and the spacer grid spring/dimples due to a flow-induced vibration of the rods. A bi-axial load cell of a cylindrical shape is specially designed. Strain gages for a special use in a high temperature condition were attached on to the sensitive region of it to accommodate the bi-axial loading condition in fretting. The full scale of this load cell is ±50 N in axial force and ±50 N in bending force, respectively. In order to increase the sensitivity and to compensate for an ambient temperature effect, the load cell consists of two Wheatstone full bridge arrangements. The calibration results of the load cell show that the coupling effects of each force were almost negligible. This paper mainly presents the experimental techniques used during the development of the new load cell system. The techniques are characterized by a design optimization of a jig of a cylindrical type, the application of a metallic sealant for a waterproofing, a free welding fabrication process and a temperature compensation circuit. Details on the development procedure, calibration method and application results are also given in this paper.
Authors: Hao Wang, Yi Shan Zhang, Shen Fang Yuan
Abstract: Crack and strain detecting is an important part of Structure Health Monitoring for aircrafts in fatigue environment. A signal conditioning circuit of a new strain-crack detecting system is developed in this paper. This circuit can deal with both intelligent coating sensor and strain gage, which have a great different original resistance between the two kinds of sensors. Comparing to the Wheatstone Bridge, when the strain is being detected, the new circuit gets rid of the influences of the lead-wires and decreases the wires’ number. The principle and the constitution of the circuit are introduced. And the circuit’s performances are demonstrated by a series of experiments. The linearity error is small and the stability is good.
Authors: Luciano Arruda, Cristiano Coimbra, João Marco Andolfatto
Abstract: This work is related to reliability of strain measurement in flexible printed circuit boards (fPCBs) made with polyimide substrate. It was observed that the fPCBs are very sensitive to strain mounting stiffness. The indirect measurement method will be done employing High Speed Camera (HSP). The direct method will be formulated in two ways: 1) conventional strain gauge glued in an fPCBs; 2) printed strain gauge in a polyimide substrate. This paper will point out mistakes and show advantages when using different method to extract the deformation field of the selected area in a flexible thin film.
Authors: Young Seon Lee, J.H. Lee, Yong Nam Kwon, T. Ishikawa
Abstract: The dimension of cold forged part is larger than that of the die cavity. The difference could be originated from the various features, such as the elastic characteristics of die and workpiece, thermal influences, and machine-elasticity. Among these features, elastic behavior of die and workpiece has been considered as the most important element for the precision cold forging. In the present study, the effect of material properties of both workpiece and die on the dimensional precision of forged part was investigated using FE and experimental analyses. Three materials, such as SCM420H, Cu-OFHC and Al6061 alloy, were used to divide the effect of the elastic modulus and flow stress on the dimension specifically. From the results of FEA, the elastic deformation of die was found to be more dominant than that of workpiece. The die expansion depends on the flow stress of workpiece during a loading stage. On the other hand, the die contraction during unloading was affected by both the flow stress and elastic modulus of workpiece. The elastic modulus of workpiece affects the elastic recovery of forged part after ejecting stage.
Authors: Hrushikesh Sarangi, K.S.R.K. Murthy, Debabrata Chakraborty
Abstract: The accuracy of measurement of opening mode stress intensity factor using strain gage techniques mainly depends on location of the strain gages. The present work proposes a finite element based simple procedure for accurate determination of three parameter zone and optimum strain gage location for various eccentric cracked configurations. In this paper, the effect of specimen size and crack length to width of the eccentric cracked plate on optimum location of strain gage is also studied. The results of the present investigation show that specimen size and ratio of crack length to width of the plate strongly influence the optimum location of strain gage.
Authors: Eduard Schenuit, Rainer Bolkart, Thomas Becker, Oliver Spinka
Abstract: Progresses in developments of high resolution digital cameras and processors power as well enable the use of optical systems for axial and biaxial strain measurements. The main benefit of these systems is a contact free measurement on the sample surface without any influence to the sample. The commonly used optical systems based on following markings attached to sample surface which have to be applied before testing. This paper presents an alternative optical measuring system using the speckle-correlation-technique. The laser based method does not need any special sample markings before testing. The speckle correlation in the presented extensometer measures up to two-dimensional surface strains in tensile as well as in compression tests; original gauge lengths down to 1.5 mm are supported.
Showing 1 to 10 of 16 Paper Titles