Strain Gauge Sensors Research Articles

COMPARATIVE ANALYSIS OF HATCH COVER STOCKING GANTRY CRANE HOOKS MANUFACTURED FROM ST37 AND WELDOX700 STEELS UNDER STATIC LOADING CONDITIONS

Crane hooks are used to ensure the safe transportation of loads to be lifted in load lifting and handling systems. In this study, special hooks for cranes designed to open and close the doors of warehouse zones used for ship cargo and cargo transport, and their responses under 60,000 N static loading conditions are numerically and experimentally analyzed. In the experimental study, ST37 structural steel and Weldox700 high-strength steel were used to manufacture the hook. Experimental data collected under static loading conditions of the component was measured via strain gauges sensors. It was concluded that the results of structural numerical analysis with the Finite Element Method (FEM) using ANSYS 2019 R3 analysis program with experimental data are in harmony with the results of experimental measurements. In addition, the maximum values of stress of the hook manufactured with Weldox700 and ST37 steels under the stress static loading conditions are obtained as 60 MPa and 57.3 MPa, respectively. In the numerical analysis results, stress value was obtained as 61.21 MPa. Compared to the analysis results based on experiments and FEM, numerical analysis results showed that fudge factors in ST37 and Weldox700 steels are 1.8% and 6%, respectively. This result confirms that experimental and mathematical data were in harmony with each other and reliable.

Maximum deflection of simple span steel box girder bridge using stress data

The Structural Health Monitoring System is part of tool and method for bridge operation and maintenance to make sure that the bridge is in good condition. Deflection is one of the main parameters to be measured and various methods has been introduced to measure deflection. Accuracy and economically are two main aspects when selecting the method for determine the real time deflection. This study presents a method of determining the maximum deflection of simple span continuous bridge using strain data obtained from a strain gauge sensor for simple span steel box girder bridge. Initial data were obtained from FEM simulations under various load conditions to obtain the maximum deflection value and the strain value. Linear regression and quadratic regression were carried out to obtain the relationship between the strains data and the maximum deflection. The accuracy of the maximum deflection value is then compared with the results of the analysis using FEM. It was found that the accuracy is about 91.16 % for quadratic regression and 9.07 for linear regression 90.93 %.

Моделювання варіантів транспедикулярної фіксації грудного відділу хребта при резекції одного-трьох хребців

Актуальність. Патологічні переломи хребців є найбільшим ускладненням пухлинного процесу. Застосування додаткової внутрішньої фіксації металевими імплантатами значно покращує результати лікування й скорочує строки реабілітації хворих. Використання транспедикулярних пристроїв забезпечує стабільну фіксацію й стабільність сегментів хребта навіть при максимальному ступені його нестабільності. Мета: визначення оптимального варіанта протяжності заднього спондилодезу при паліативному та радикальному хірургічному лікуванні пухлин хребта. Матеріали та методи. Для вивчення можливостей стабілізації за допомогою транспедикулярної фіксації при резекції одного-трьох хребців провели експериментальні випробування на препаратах хребта свині. Використовували препарати сегментів грудного відділу хребта від Th3 до Th12 хребців. Вивчали 3 групи моделей: з одним резектованим хребцем Th6, з двома — Th5-Th6 і з трьома — Th5-Th7. Результати. Виявлено, що при резекції одного хребця в грудному відділі хребта транс-педикулярна фіксація за схемами 111х111, 101х101 та 011х110 має однакову ефективність. При резекції двох хребців найкращі стабілізуючі можливості мала конструкція за схемою 111хх111, схеми 101хх101 та 011хх110 показали доволі непогану фіксуючу здатність. При резекції трьох хребців грудного відділу хребта найбільш стабільну фіксацію показала схема 111ххх111. Схема фіксації 001ххх100 виявилась нестабільною при всіх видах резекції хребців. Висновки. Експериментальні дослідження транспедикулярної фіксації при радикальному хірургічному лікуванні пухлин хребта, який включає резекцію одного-трьох хребців, показали, що конструкція відповідає вимогам фіксації, коли кріплення відбувається не менше ніж за два верхніх та два нижніх хребці (можна через один), при резекції трьох хребців найбільш стабільною є конструкція з кріпленням за три верхні та три нижні хребці (без пропусків). Система кріплення за один хребець виявилася неспроможною майже при всіх видах резекції.

Design, Simulation, Implementation and Measurement of Respiration Rate by Strain Gauge Sensor and Induction Method

The human body has vital parameters such as respiration, heart rate, and body temperature. Respiratory rate (RR) is a parameter that expresses the rate of respiration per minute. Respiratory activities play an essential role in human life. The rate of respiration has a particular range, which is 14-18 cycles per minute for a healthy and normal person at rest. The oxygen in the blood enters the body during respiration and is expelled as carbon dioxide in return. Any problems with breathing may pose a serious health risk. An abnormal breathing pattern indicates serious illnesses such as cardiac arrest and hospitalization in the intensive care unit (ICU) and when it falls below a certain limit, it indicates a loss of consciousness. This is why it is so imperative to develop devices and methods measuring respiration rates.

Evaluation of strain measurements using ZnS: Mn, Cu as mechanoluminescent material and strain gauge sensor

Structural health monitoring (SHM) is emerging as a significant aspect in structural engineering. Predominantly, civil engineering structures have become more reliant on SHM. Advanced sensors and smart materials are the prominent technologies for applying Structural Health Monitoring. Numerous techniques for damage detection of the structures in the field of civil engineering. In this paper, we have introduced innovative smart material, Mechanoluminescent material that enables real-time continuous monitoring and damage detection of the structures. The most prominent ML (Mechanoluminescent material) Mn (Manganese) or Cu (Copper) doped ZnS (Zinc sulphide) crystal is studied because they exhibit the brightest luminescent emission. The present investigation aims to evaluate the strain measurements using ML material and compare the readings with the strain gauge sensor obtained in the Arduino Integrated Development Environment Software (IDE). An experimental approach has been done to produce ML material and to understand the fundamental ML phenomenon. At present, many researchers have developed ML material for the implementation to real-social infrastructure. If success leads the ML material will be a new step for development of modified sensor channel that could monitor a structure for actual impacts with the existence of stress levels acting on it.

Micro deformation measurement using flexible and ultra-thin glass sheet cantilever

Micromechanical characterization evaluation of single cells, such as elastic, young’s modulus and stiffness is of fundamental importance to the study of cell growth, differentiation, migration and morphogenesis. However, traditional methods (such as atomic force microscope or optical stretching methods) are time-consuming, complicated or low sensitivity. Device with the fast response and high sensitivity still remains challenging. Glass-based devices made of ultra-thin glass sheets are transparent and physically and chemically stable, which allows high resolution and real-time observation of cell deformability. Here a micro-indentation method using an ultra-thin glass sheet (UTGS) cantilever platform integrated with the metallic foil pattern as the strain gauge sensor provides a way to measure the micro deformation under 30 μm which could be used to measure the stiffness of single cells in the future.

Design a Building Information Modeling (BIM) project concept in combination with foundation monitoring on the example of the Abu Dhabi Plaza construction project

With the advent of new technology in the monitoring of buildings and highrise structures it has become possible to monitor damage and defects in existing structures and infrastructures. The need for timely detection of critical points of building structure defects through the use of sensors, as well as the lack of description tools for understanding, visualizing and documenting sensor output data increasingly encourages designers, builders and facility managers to use the capabilities of such a powerful system as the Building Information Modeling System (BIM). The primary goal of any construction project is safety for people, which can only be ensured by proper monitoring of building health, where the presentation and management of the received information about changes in the system and structure can be ensured by using BIM. The purpose of this paper is to describe the application of a distributed fiber optic strain gauge sensor system, and the possibility of integrating the data obtained from the sensors into the BIM system.

Machine Learning Methods for Automatic Silent Speech Recognition Using a Wearable Graphene Strain Gauge Sensor.

Silent speech recognition is the ability to recognise intended speech without audio information. Useful applications can be found in situations where sound waves are not produced or cannot be heard. Examples include speakers with physical voice impairments or environments in which audio transference is not reliable or secure. Developing a device which can detect non-auditory signals and map them to intended phonation could be used to develop a device to assist in such situations. In this work, we propose a graphene-based strain gauge sensor which can be worn on the throat and detect small muscle movements and vibrations. Machine learning algorithms then decode the non-audio signals and create a prediction on intended speech. The proposed strain gauge sensor is highly wearable, utilising graphene’s unique and beneficial properties including strength, flexibility and high conductivity. A highly flexible and wearable sensor able to pick up small throat movements is fabricated by screen printing graphene onto lycra fabric. A framework for interpreting this information is proposed which explores the use of several machine learning techniques to predict intended words from the signals. A dataset of 15 unique words and four movements, each with 20 repetitions, was developed and used for the training of the machine learning algorithms. The results demonstrate the ability for such sensors to be able to predict spoken words. We produced a word accuracy rate of 55% on the word dataset and 85% on the movements dataset. This work demonstrates a proof-of-concept for the viability of combining a highly wearable graphene strain gauge and machine leaning methods to automate silent speech recognition.

SMA AS MEANS FOR SENSITIVE BIOMEDICAL SENSORS

Shape memory alloys (SMA) are materials with specific electric, mechanic and thermal qualities originating in their microscopic structure and as such are used to design so-called Smart structures. In biomedicine, they are used mostly for their shape memory properties during intravasal surgery. The commonly used SMA material for biomedical purposes is Nitinol, a nickel-titanium alloy that exhibits, especially when annealed, among other properties also superelasticity and high resistivity with strain changes. This makes it suitable for usage in strain gauge sensors. In this work, NiTi annealed wires were used to create a strain gauge sensor, which exploits their unique properties. The properties of these sensors were then described using a climatic chamber, stretching device and a set of weights. Those properties were then compared to similar sensors, that are using different principles. The development, that followed, used these sensors in particular biomedical applications.

중형 유조선의 프로펠러 추력변동이 축 거동에 미치는 영향 연구

The movement of the propeller shaft shows different changes in each condition, such as static, dynamic, and transient, mainly based on changes in propeller eccentricity due to changes in engine load. In general, this contributes to changing the bearing load of the shaft at the after stern tube bearing, and in severe cases causes damage to the stern tube bearing. To prevent this, various research regarding pragmatic designing on shafting system has been carried out focusing on optimize the relative inclination and retain the oil film thickness between the shaft and the stern tube bearing. However, in order to secure the integrity of the support bearing from damage, it is necessary to additionally consider dynamic conditions including transient conditions such as sudden alteration in the stern wake-field. In this context, this study cross validated the effect of propeller shaft movement during starboard turning of a medium range oil tanker at full laden draft using the strain gauge and displacement sensor. As a result of the analysis, it was confirmed that the propeller thrust fluctuation temporarily increased the load on the stern tube bearing.

Experimental and Numerical Investigation of Bond-Slip Behavior of High-Strength Reinforced Concrete at Service Load

A bond mechanism at the reinforcement-concrete interface is one of the key sources of the comprehensive functioning of reinforced concrete (RC) structures. In order to apprehend the bond mechanism, the study on bond stress and slip relation (henceforth referred as bond-slip) is necessary. On this subject, experimental and numerical investigations were performed on short RC tensile specimens. A double pull-out test with pre-installed electrical strain gauge sensors inside the modified embedded rebar was performed in the experimental part. Numerically, a three dimensional rib scale model was designed and finite element analysis was performed. The compatibility and reliability of the numerical model was verified by comparing its strain result with an experimentally obtained one. Afterwards, based on stress transfer approach, the bond-slip relations were calculated from the extracted strain results. The maximum disparity between experimental and numerical investigation was found as 19.5% in case of strain data and 7% for the bond-slip relation at the highest load level (110 kN). Moreover, the bond-slip curves at different load levels were compared with the bond-slip model established in CEB-fib Model Code 2010 (MC2010). Overall, in the present study, strain monitoring through the experimental tool and finite element modelling have accomplished a broader picture of the bond mechanism at the reinforcement-concrete interface through their bond-slip relationship.

© ПНИПУ Numerical and experimental research of the evaluation of the mechanical behavior of carbon fiber reinforced polymerspecimens with an embedded Smart-layer

Currently, scientists have paid special attention to the possibility of creating so-called Smart-structures that are capable of real-time self-diagnostics and/or functional changes. Within the framework of this work, the possibility of creating structures capable of diagnosing the deformation state in real-time is considered. When creating such Smart-structures, fiber-optic, piezo-, and strain-gauge sensors are usually used as control sensors. The use of such sensors is due to a number of their advantages, such as small size, the ability to integrate into a single measuring network, ease of use, a wide range of measured values, the ability to transmit data over long distances. However, when such sensors are embedded into the structure, several difficulties arise in installation/dismantling or implementation due to the fragility of the fiber, the difficulty of locating the sensitive element, ensuring the integrity of the fiber-optic sensors at the exit from the polymer structure. The team of the Scientific and Educational Center of Aviation Composite Technologies, PNRPU, has developed a prototype of a Smart-layer based on 3D-printing technology, capable of solving the problems described above. However, the influence of such an embedding on the structure of structures made of carbon fiber reinforced polymer (CFRP) remains open. Thus, this work aims to carry out computational and experimental studies to assess the mechanical behavior of CFRP samples with an embedded Smart-layer. Within the framework of this work, the technology and scheme for manufacturing a Smart-layer with embedded fiber-optic sensors, as well as a scheme for laying a Smart-layer into CFRP samples, are described. Since the properties of molded plastic specimens differ from those of printed specimens, mechanical tensile tests of printed specimens were carried out. The obtained values of the strength limit and the modulus of elasticity were used to identify the mathematical model. Within the framework of the experimental part, mechanical tests for tension, compression, and interlayer shear of CFRP samples with an embedded Smart-layer were carried out. When analyzing the obtained experimental results, it was found that the maximum percentage deviation of the physical and mechanical characteristics (PMC) is no more than 15 %, which lies within the spread of the PMC of carbon fiber in a prepreg roll. As a result, we can conclude that the embedded of such Smart-layers does not significantly affect the PMC of the final CFRP structure. According to the results of mathematical modeling of the tensile strength of a CFRP sample with an embedded Smart-layer, it was found that the maximum value of normal stresses in the sample reaches 540,28 MPa, which is 1,46 % higher than the maximum value for the statistical ultimate strength of the sample. The maximum values of the Mises stress for the Smart-layer do not exceed the ultimate strength, while for the epoxy binder there is a significant excess of the ultimate strength, on the basis of which one can make an assumption about its destruction during deformation.

In operando measuring circumferential internal strain of 18650 Li-ion batteries by thin film strain gauge sensors

The state-of-the-art Li-ion batteries undergo severe performance degradation caused by the mechanical failure of the internal jelly roll structure. It is a long-standing challenge to in-situ and real-time measure internal deformation of the electrodes inside the jelly roll structure because of the harsh environment in the Li-ion battery and tight jelly roll structure in the confined space. In this paper, an in-situ internal strain measurement method in the 18650 Li-ion battery is developed. A newly designed strain gauge sensor and a novel integrated method are proposed, which is compatible with the 18650 Li-ion battery assembly process, allowing the integrated 18650 Li-ion battery for delivering stable performance compared with the regular 18650 Li-ion battery. We demonstrate for the first time the evolution of the internal strain in the 18650 Li-ion battery during the charging and discharging processes. The strain changes are divided into three stages during the charging/discharging, which are mainly dominated by the interlayer spacings transition of the negative graphite electrode during the lithiation/delithiation. Finally, the proposed method is a promising tool for fundamentally understanding the internal strain evolution and safety designed of the LIBs under more realistic operation conditions.

A Flexible Chip-Film Patch and a Flexible Strain Gauge Sensor Suitable for a Hybrid System-in-Foil Integration

Hybrid Systems-in-Foil (HySiF) encompass large-area thin-film electronics and ultrathin, high performance CMOS chips, which are integrated into a flexible polymeric foil substrate. In this work, the individual components of a customized flexible sensor system are characterized in detail, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e.</i> , a strain gauge and a readout ASIC, and the system functionality is proved. We employ the Chip-Film Patch (CFP) technology, where an ultra-thin readout ASIC is embedded in spin-coated polyimide foil in order to monitor resistance variations of strain gauges. These two components are suitable to be integrated on the same foil, whereas the envisioned system is intended to monitor the respiratory system of newborns and premature infants. The latest developments in the CFP process using the aromatic polyimide PI-2611 are shown. In particular, the optimization of the spin-coating and evaluation of polyimide uniformity above the embedded chip are highlighted. Furthermore, we demonstrate a flexible strain gauge sensor using thin-film metals embedded in polyimide PI-2611, which is usable at up to 30% strain under electromechanical load. This also demonstrates the mechanical reliability of the CFP circuit interconnects. The electrical characterization of the readout ASIC, after back-thinning and embedding into the CFP, reveals no stress induced performance degradation.

Performance Analysis of Plate Punching and Bending Machine Combination

The plate punching and bending combination machine is a machine that belongs to the press type with the use of a punch and a die to make holes or bends in a plate work-piece. This machine uses a hydraulic drive with a maximum working pressure of 700 Bars, which is used as a punch force to work-piece. But, it is not known the value of working pressure this frame can withstand. Therefore, machine performance becomes unknown such as punch force that can be used, work-piece thickness, whole circumference and type of material that can be machined. In this paper, the analysis is carried out using simulation and experimental methods. The simulation method is carried out using Autodesk Inventor software to determine the critical location, which is then measured by experiment. The experimental method is carried out by measuring the stress and deflection. Voltage measurement on the frame is carried out using a strain gauge sensor and measurements are carried out using a dial indicator. The application of a safety factor is 1.5 based on the yield strength of ASTM A36 as the frame material. The deflection that has occurred is 1.15 mm, the maximum working pressure obtained is 27.7 Bars. The maximum punch force is 5441 N.

Fractional Control of a Lightweight Single Link Flexible Robot Robust to Strain Gauge Sensor Disturbances and Payload Changes

In this paper, a method to control one degree of freedom lightweight flexible manipulators is investigated. These robots have a single low-frequency and high amplitude vibration mode. They hold actuators with high friction, and sensors which are often strain gauges with offset and high-frequency noise. These problems reduce the motion’s performance and the precision of the robot tip positioning. Moreover, since the carried payload changes in the different tasks, that vibration frequency also changes producing underdamped or even unstable time responses of the closed-loop control system. The actuator friction effect is removed by using a robust two degrees of freedom PID control system which feeds back the actuator position. This is called the inner loop. After, an outer loop is closed that removes the link vibrations and is designed based on the combination of the singular perturbation theory and the input-state linearization technique. A new controller is proposed for this outer loop that: (1) removes the strain gauge offset effects, (2) reduces the risk of saturating the actuator due to the high-frequency noise of strain gauges and (3) achieves high robustness to a change in the payload mass. This last feature prompted us to use a fractional-order PD controller. A procedure for tuning this controller is also proposed. Simulated and experimental results are presented that show that its performance overcomes those of PD controllers, which are the controllers usually employed in the input-state linearization of second-order systems.

Application of Operational Load Monitoring System for Fatigue Estimation of Main Landing Gear Attachment Frame of an Aircraft.

In this paper, we present an approach to fatigue estimation of a Main Landing Gear (MLG) attachment frame due to vertical landing forces based on Operational Loads Monitoring (OLM) system records. In particular, the impact of different phases of landing and on ground operations and fatigue wear of the MLG frame is analyzed. The main functionality of the developed OLM system is the individual assessment of fatigue of the main landing gear node structure for Su-22UM3K aircraft due to standard and Touch-And-Go (T&G) landings. Furthermore, the system allows for assessment of stress cumulation in the main landing gear node structure during touchdown and allows for detection of hard landings. Determination of selected stages of flight, classification of different types of load cycles of the structure recorded by strain gauge sensors during standard full stop landings and taxiing are also implemented in the developed system. Based on those capabilities, it is possible to monitor and compare equivalents of landing fatigue wear between airplanes and landing fatigue wear across all flights of a given airplane, which can be incorporated into fleet management paradigms for the purpose of optimal maintenance of aircraft. In this article, a detailed description of the system and algorithms used for landing gear node fatigue assessment is provided, and the results obtained during the 3-year period of system operation for the fleet of six aircraft are delivered and discussed.

A Sensor for Measuring the Tension of Cotton Belt

In this paper, the design process of a strain gauge sensor for measuring the tension of cotton belt is presented. The elastic body of the sensor is a single cantilever beam, and a light metal pulley is installed at the end of the beam. When the cotton belt passes through the pulley, the pulley will be subjected to pressure and cause the deformation of the beam. After processing, the electrical signals output by the resistance strain gauges pasted on the elastic body can be converted into the tension of the cotton belt. In this study, first of all, through mechanical calculation, it is determined that there is an approximate linear relationship between the change of the tension of the cotton belt and the output signal of the bridge of the elastomer. Then, through the finite element method, the relationship between the strain of the elastomer and the pressure on the guide wheel is analyzed, and the specific size of the elastomer and the appropriate position of the resistance strain gauge are determined. Finally, the temperature compensation and broken line correction are carried out. The practice shows that the measuring range of the sensor can reach 30N, the sensitivity can reach 2.35mV/V, the maximum linear speed of the 6 mm wide cotton belt passing through the guide wheel of the sensor can reach 2m/s, the working temperature range of the sensor is -30~60°C, and the comprehensive measurement error is less than 0.5%F.S.

Strain Sensor’s Network for Low-Velocity Impact Location Estimation on Carbon Reinforced Fiber Plastic Structures: Part-II

Identification of low velocity impact (LVI) location in composite aircraft structures is seamless need for safe, reliable operation and maintenance of aerospace industry. To locate the LVI’s an optimized sensor network has designed using the strain response from fiber Bragg grating (FBG) & resistance strain gauge (RSG) sensor bonded to the composite structure. Strain scan (SS) algorithm has been developed to locate such events reported as Part-I. In this work, we have developed a novel algorithm based on weighted energy (WE) of the sensor response. The LVI’s has been carried out on composite structures & the locations of LVI’s have estimated using SS, WE & previously developed machine learning base support vector machine (SVM) algorithms. The WE and SS algorithms are based on proximity of events (closer to the sensor, higher the response), whereas LS-SVR is a data-driven approach. Further, we have compared the performance of the developed algorithms and algorithms cited in the literature using the performance index (PI), a measure of estimation efficiency as a function of the number of sensors, dimension/area of the structure, error & number of test cases. It is established that WE algorithm shown suprema performance over the other algorithm with 34 mm mean Euclidian distance error & PI value of 5.5.

Space-Filling Curve Resistor on Ultra-Thin Polyetherimide Foil for Strain Impervious Temperature Sensing.

Monitoring process parameters in the manufacture of composite structures is key to ensuring product quality and safety. Ideally, this can be done by sensors that are embedded during production and can remain as devices to monitor structural health. Extremely thin foil-based sensors weaken the finished workpiece very little. Under ideal conditions, the foil substrate bonds with the resin in the autoclaving process, as is the case when polyetherimide is used. Here, we present a temperature sensor as part of an 8 µm thick multi-sensor node foil for monitoring processing conditions during the production and structural health during the lifetime of a construction. A metallic thin film conductor was shaped in the form of a space-filling curve to suppress the influences of resistance changes due to strain, which could otherwise interfere with the measurement of the temperature. FEM simulations as well as experiments confirm that this type of sensor is completely insensitive to the direction of strain and sufficiently insensitive to the amount of strain, so that mechanical strains that can occur in the composite curing process practically do not interfere with the temperature measurement. The temperature sensor is combined with a capacitive sensor for curing monitoring based on impedance measurement and a half-bridge strain gauge sensor element. All three types are made of the same materials and are manufactured together in one process flow. This is the key to cost-effective distributed sensor arrays that can be embedded during production and remain in the workpiece, thus ensuring not only the quality of the initial product but also the operational reliability during the service life of light-weight composite constructions.