Inductive Sensor Research Articles

Integration of sensors in sandwich composites for the detection of structural damage

A decisive factor in achieving the climate targets of the German government is the reduction of CO2 through the gradual electrification of transport. In battery-electric vehicles, the energy storage system is typically positioned close to the ground under the passenger cell. Thus, the crossing of obstacles or typical load scenarios affecting the underbody play a crucial role for vehicle safety. Currently, such battery protection structures usually consist of thick-walled aluminum, steel or titanium constructions, which results in increased weight and manufacturing costs [1]. Higher moving masses in battery electric vehicles lead to high resource consumption in their life cycle. In this context, battery protection structures represent lightweight structures that are safety critical parts protecting the battery system from impact events and medial influences. Additionally, these parts are in general large-scale parts, which show a high potential for mass reduction and functional integration of a conditions monitoring system. Therefore, the focus of the presented paper is on the development of a functionally integrative lightweight battery protection structure, which consist of a sandwich lay-up of glass fiber reinforced plastic (GRP) cover sheets and polymeric foam in the middle. In addition to the purely mechanical protection of the energy storage unit, this structure should be able to detect and classify any damage occurring of the battery module above it caused by impact events. Thus, a structure-integrated sensor system is also focused, which shall be used for the determination of the extent of damage, which means that service activities or component replacements will only be carried out when necessary and not within predefined maintenance intervals. Based on a detailed requirement profile for the structure, a comparison of selected sensor concepts is carried out. For further investigations, three sensor types (pressure sensor, strain sensor, inductive sensors) are selected and examined in more detail. Thus, investigations in regard to the sensor positioning in the composite lay-up and the ability for detecting different load cases were planned and carried out. A further issue is the clarification of possible integration options in terms of manufacturing technology. For this purpose, the so-called e-preforming technology is used, which enables an automated application of functional elements. Therefore, different types of conductor track manufacturing and contacting of electronic components within the sandwich structure are investigated. The results of these initial investigations in the case of automotive applications show a high potential to be transferred to applications in the aviation or aeronautical industry. In particular, these also influence the approaches for the design and development of structural health monitoring components and systems.

Additive manufacturing of inductive force sensor with NiZn-ferrite magnetic core for robotic gripper

Additive manufacturing of inductive force sensor with NiZn-ferrite magnetic core for robotic gripper

Wear Debris Sensor Using Intermittent Excitation for High Sensitivity, Wide Detectable Size Range, and Low Heat Generation

A highly sensitive inductive wear debris sensor based on intermittent excitation is presented for real-time condition monitoring of machinery faults. The specially designed intermittent excitation method utilizes short-term large currents to periodically generate a strong alternating magnetic field, thus attaining enhanced sensitivity and low heat generation at the same time. A combination of different excitation currents is also applied for multi-sensitivity measurement to expand the detectable size range and detection accuracy, which is suitable for industrial occasions with complex detection requirements. In order to verify the effectiveness of intermittent excitation, a sensor prototype and signal processing system have been constructed. The testing results demonstrate that the sensitivity of the proposed sensor using intermittent excitation with a duty cycle of 1% is 10 times that of constant excitation with the same power consumption. A wide detectable size range of 48 µm-1426 µm iron particles and 112 µm-3802 µm copper particles in a 10 mm diameter sensing channel have been realized by dual-sensitivity measurement with outstanding temperature stability and size accuracy. The design concept of intermittent excitation can be extended to various types of debris sensors and other online detection equipment for great performance improvement.

Optimization of the Cell Constant for Application of the Transformer Type Inductive Conductivity Sensor (TICS) in Low-Conductive Solution

In this paper, the relation between geometry of a TICS (inner radius r1, outer radius r2 and height t of the sensor toroid) and its cell constant is presented through simulation analysis by the finite element method and experiments. Taking account of actual condition, sizes (r1, r2 and t) of the sensor are considered within several tens mm. A key factor which influences on the cell constant is a hole diameter (2r1) of the sensor toroid. The effective superior limit of inner radius of the sensor toroid that can give the smallest cell constant is about 30 mm. Theoretical results on the cell constants of sensors with different sizes corresponded to the experiment results with less than about 5% relative error. Conductivity below limit value which can be adjusted by cell constant is about 0.36 times of the lowest bound value of conductance measurement range.

Development of the Metal and Non-Metal Waste Sorting System Design by using an Arduino Uno

A material is waste if it has been utilised and no longer desired. Waste needs to be appropriately managed and disposed of. However, most of the waste is not effectively managed and disposed of. As a result, it has brought up certain difficulties, such as environmental pollution, which can affect human health. Every year, more waste is produced around the world, and not all parties are aware of the importance of maintaining environmental cleanliness by making solid waste segregation a daily practise. In this regard, several initiatives have been taken by the government, such as introducing various campaigns towards a better environment, such as the 3R concept (Reduce, Reuse, Recycle) as well as the solid waste separation campaign. This paper presents the design and development process of a waste sorting system that can separate metal and non-metal materials by using an Arduino UNO. The benefit of this system is that it has a notification system that may alert the person or entity in charge when the trash in the bins is full. The system's design and development go through four major phases. Phase 1 is the design of the circuit, Phase 2 is the development of the Arduino Uno coding and simulation; Phase 3 is the assembly, testing, and prototype development; and Phase 4 is the results analysis. This system is a complete success. When detecting metal and non-metal materials, all three input components—the proximity sensor, the IR sensor, and the ultrasonic sensor are fully functional. The servo motor will move the non-metal material to the right side of the bin if the IR sensor detects non-metal material, and if the inductive proximity sensor detects metal material, the servo motor will move the metal material to the left side of the bin, ensuring that waste is separated properly.

500 MHz high resolution proximity sensors with fully integrated digital counter

We report on the design and characterization of two inductive proximity sensors based on LC oscillators operating at 500 MHz. The distance from the target is obtained by measuring the oscillation frequency variation. Both sensors contain an off-chip LC resonator consisting of a two turns 4 mm diameter planar coil and a ceramic capacitor. The LC resonator is connected to integrated CMOS electronics. The first sensor output stage consists of a buffer whereas the second sensor output stage includes a co-integrated 21 bits digital frequency counter. The first sensor has frequency noise floor of 0.085 Hz/Hz above 3 kHz. At a distance of 200 μm from the coil, the resolution is 0.2 pm/Hz and the integrated resolution from 1 mHz to 1 kHz is 22 pmrms. The second sensor reaches a noise floor of 2 Hz/Hz corresponding to a resolution of 5 pm/Hz and an integrated resolution of 900 pmrms.

Simulation and Optimization Design of Inductive Wear Particle Sensor.

In order to monitor the diagnosis of mechanical equipment by monitoring the metal wear particles carried in large aperture lubricating oil tubes, the simulation optimization structure design was carried out based on the traditional three-coil inductance wear particle sensor. The numerical model of electromotive force induced by the wear particle sensor was established, and the coil distance and coil turns were simulated by finite element analysis software. When permalloy is covered on the surface of the excitation coil and induction coil, the background magnetic field at the air gap increases, and the induced electromotive force amplitude generated by wear particles is increased. The effect of alloy thickness on the induced voltage and magnetic field was analyzed to determine the optimum thickness, and increase the induction voltage of the alloy chamfer detection at the air gap. The optimal parameter structure was determined to improve the detection ability of the sensor. Ultimately, by comparing the extreme values of the induced voltage of various types of sensors, the simulation determined that the minimum allowable detection of the optimal sensor was 27.5 µm ferromagnetic particles.

Выбор методов постоянного мониторинга крутильных колебаний в судовых машинно-движительных комплексах

The article considers the problem of the continuing emergency damages to the elements of ship engine-propulsion systems with fatigue failures of shaft pipelines. The classification societies require to analyze and measure the dangerous torsional vibrations in ship power plants. There is given an overview and comparison of methods of measuring torsional vibrations in order to determine the most promising ones for constant monitoring and diagnostics of the technical condition of the elements of marine propulsion systems. In the course of analysis of scientific and technical literature there have been identified the main methods of measuring torsional vibrations, which formed the basis for developing the national and foreign measuring software and hardware complexes. The marine conditions surely require the appropriate design and operating principles from the monitoring systems, therefore, such methods as strain measurement, using laser and optical sensors with reflective tape, inductive sensors with gears are defined as promising. There is illustrated a diagram of the measuring bridge of four load cells, given an example of the design and positioning of the IVC Technologies strain gauge system on the shaft, considered the Geislinger systems with a spring damper and measuring gears. There are presented the illustrations of the OROS measuring system, the Konsberg system, the RT-660 radiotorsiograph, the SCAN optical torsiograph developed by JSC Central Research and Design Institute of the Marine Fleet (TsNIIMF), the TNK-1 sensor, the BAGS-4M measuring complex and others. The results of the study will be used to develop experimental samples of a monitoring system with the selected methods for measuring torsional vibrations and conducting tests in the laboratory and on board a ship.

Noise reduction by using wavelet transform in charge signal acquired from an electrostatic inductive sensor

Noise reduction by using wavelet transform in charge signal acquired from an electrostatic inductive sensor

Increasing the accuracy of the process of automated counting of thin long products

Vibrating hopper feeders with an electromagnetic drive for automating the process of counting parts have become widely used. This process is necessary when transferring them to another workshop for the next technological operation. Also, it is necessary to count artificial products on the lot when packing them for packaging. Vibrating feeders are used to feed miniature, small, or medium-sized parts to the counting position of counting or packing machines. In this case, the parts supplied to these positions should be arranged in one layer. In addition, they should have a certain gap between them for reliable operation of the counting device. Basically, counters for such machines are made on the basis of photoelectric or inductive sensors. The disadvantage of inductive sensors is that they can only be used for metal objects. Photoelectric sensors are more versatile, so they have gained the most distribution for counting or filling machines. The principle of operation of the automatic counting position is that when the object to be counted is applied to it, it crosses the working area of the counting position and the sensor sends an impulse to the counting device. When using photoelectric sensors, parts or products cross the beam of the sensor and it supplies a counting pulse to the electronic counter at each crossing of the working beam. Basically, when using vibrating hopper feeders, the counting position is located either directly at the exit part of the transporting tray, or at the exit from it of the transported objects. The speed of transporting parts or products increases when moving up, because the amplitude of the horizontal component of oscillations increases when the diameter of the transporting tray increases. This is because the hopper of the vibratory feeder has a conical shape. This allows the parts to be refined in one layer. In addition, before the counting position, the parts must be separated from each other to create the necessary gap between them. This is necessary for the reliable operation of the photoelectric sensor. This system works reliably when the dimensions of the parts to be counted are larger than the diameter of the working beam of the sensor. But, when automating the counting of thin, long parts or products whose thickness is close to the size of the working beam of the sensor, the latter may cross it several times when passing through the zone of the counting position. This sharply reduces the accuracy of the counting process. This happens because the parts on the conveyor tray move with a small bounce due to the vertical component of the hopper's vibrations. Therefore, it became necessary to develop a new counting position system in order to increase the accuracy of the counting device for counting long thin parts or products (pins for electrical connectors, needles, matches, etc). The work considers a set of elements that affect the productivity and efficiency of counting devices based on vibrating hopper feeders with electromagnetic drives, for counting long thin parts or products of this shape.

A numerical and experimental investigation of mitigation of the vibration in a structure using single pendulum type mass damper

The main objective of the present work is that to construct a combined Pendulum Type Mass Damper (PTMD) in a structure to demonstrate the effect of damping of vibrations. In order to achieve this, a simple prototype has been developed. An inductive proximity sensor has been used to measure the vibrations of prototype with the PTMD system in terms of the induced voltage signal. The induced voltage signals have been acquired by using an Arduino UNO controller board. The experiments have been carried out to measure the amplitude of displacement of the vibrations in the structure in terms of voltage signals for two cases: (i) Without adding the damper or tuned mass and (ii) With adding the damper or tuned mass of 100 g, 150 g, 200 g, 250 g and 300 g respectively. However, this work reports the experimental results only for 250 g. The theoretical analysis of PTMD has been studied and presented in this paper. A numerical model for the combined pendulum type mass damper with the structure has been developed by using MATLAB SIMULINK. A series of simulations have been carried out for the various values the mass ratio, μ = 0, 0.25, 0.5, 0.75 and 1 to show the effect damper or tuned mass on the vibrations of the structure. The simulation results of amplitude of displacement of the structure have been analyzed and presented in both time domain and frequency domain. By keeping the same condition of experimental analysis of 250 g damper or tuned mass, the simulations have been carried out for two cases: (i) Without absorber mass (mass ratio, μ=0) and (ii) With a damper mass of 250 g (mass ratio, μ=0.33) in order to validate the experimental results.

Fabricating Sockets With Distance Sensors for Monitoring Prosthesis Use and Socket Fit

ABSTRACT Introduction In previous research, we developed and implemented novel inductive sensors to detect the motion of a prosthesis user’s residual limb in the prosthetic socket. Materials and Methods In this article, methods for installing the inductive sensors within the wall of a prosthetic socket are described. The sensors are flexible, 32 mm in diameter, and less than 0.2 mm thick. Two sensor placement configurations are described, one to monitor prosthesis use and the other to monitor socket fit. Results The sensors are installed after the inner resin layer of the socket is completed. Installation of the sensors increases the fabrication time over that of a traditional laminated socket by about 6 hours. Conclusions A systematic and repeatable method for manufacturing prosthetic sockets with embedded distance sensors was developed to facilitate adoption of this technique. Clinical Relevance Dissemination of the fabrication technique to install inductive distance sensors in sockets may facilitate clinical research investigation using this new technology, ultimately improving decision making for treatment, diagnosis, and prognosis of health issues faced by people with lower-limb amputation.

Prototype of a Continuous Passive Motion device for shoulder rehabilitation

Continuous Passive Motion - CPM - is a therapeutic method that provides fast and safe patient rehabilitation. Considering the fact that the equipment performs the movement along with the patient, who also does it but passively, this treatment procedure can immediately be applied in the postoperative care period. Although this technique makes recovery faster, as strains will be spared from ligaments, muscles and tendons, not all clinics can offer CPM therapy due to its high cost. Bearing in mind the existence of such equipment that performs the aforementioned motion, the objective of this work was the development and manufacture of a prototype device for continuous passive shoulder movement, with costs reduced to an approximate value of USD$730.00 compared to the average price in the market which is around USD$1510.00. This difference in values would make it affordable for a greater majority of clinics and offices to purchase them and, thus, promote the accelerated timely recovery of the limb after operation, for a larger number of patients, allowing these patients to return to their daily tasks in shorter period of time. For the execution of the prototype, specific mechanical manufacturing methods, such us turning, milling and welding of materials, were applied in order to make the equipment safe and effective, provide comfort for the patient and, above all, make the device affordable for most physiotherapy clinics. The material used for the production was stainless steel, cables, pulleys, tilting automation kit and inductive sensors.

Sensing and simulation of self-inductance of a flat, circular coil in the presence of four water-based nanofluids

Inductive sensors (ISs) are extremely sensitive sensing platforms that offer high resolution and currently serve as a relatively popular sensing platform for the detection of metals, nonmetals, and semiconductors. However, in spite of wonderful usability, there is a startling lack of IS implementation as a chemical sensor. Similarly, nanofluids (NFs) have gained more traction in the past decade since the physical properties of base fluids become heightened with the addition of nanoparticles (NPs). Regardless of these advantages, both areas lack studies regarding the behavior of NFs under a magnetic field (B-field). We show how a novel technique using a high-resolution, non-invasive inductance-to-digital converter (LDC) sensor is used to detect different NFs of varying physical properties. The LDC proves highly capable of not only serving as an extremely accurate and precise chemical sensor but also allowing us to determine how exposing several NFs to an inductor's B-field affects particle behavior in solution with extremely low signal and concentration detection limits. The four NF systems contain diamond, rutile, magnetite, and gold NPs where the sensor demonstrated superior sensitivity to gold-enhanced NFs. This exciting finding followed expected theoretical trends based on Faraday's laws of magnetism, and the experimental results were validated with finite element simulations within less than 1.0% error.

Effect of the Coil Excitation Method on the Performance of a Dual-Coil Inductive Displacement Transducer.

A dual-coil inductive displacement transducer is a non-contact type measuring element for measuring displacement and is widely used in large power equipment systems such as construction machinery and agricultural equipment. However, the effect of the coil excitation method on the performance of dual-coil inductive displacement sensors has not been studied. This paper investigates the impact of different coil excitation methods on the operating performance of displacement transducers. The working principle, electromagnetic characteristics, and electrical characteristics were analyzed by building a mathematical model. A transducer measurement device was used to determine the relationship between core displacement and coil inductance. Three coil excitation methods were proposed, and the effects of the three coil excitation methods on the amplitude variation, phase shift, linearity, and sensitivity of the output signal were studied by simulation based on the AD630 chip as the core of the conditioning circuit. Finally, the study's feasibility was demonstrated by comparing the experiment to the simulation. The results show that, under the uniform magnetic field strength distribution in the coil, the coil voltage variation is proportional to the inductive core displacement. The amplitude variation is the largest for the dual-coil series three-wire (DCSTW) and is the same for the dual-coil series four-wire (DCSFW) and dual-coil parallel differential (DCPD). DCSFW has an enormous phase shift. DCSTW has the best linearity. The research in this paper provides a theoretical basis for selecting a suitable coil excitation, which is conducive to further improving the operating performance of dual-coil inductive displacement transducers.

Research on Detection Performance of Four-Coil Inductive Debris Sensor

The online monitoring of debris in oil can timely and accurately reflect the wear status of mechanical equipment. The inductive debris sensor based on the electromagnetic induction can effectively detect various parameters of debris. The four-coil structure-based of the sensor is theoretically introduced. The optimal coil length, the turns of the excitation coil and the turn ratio are obtained through simulation in order to improve the sensitivity of the inductive debris sensor. The effects of the excitation frequency and the movement velocity, size, position and material of the debris on the sensor output are investigated. The sensing signal recovered by coherent demodulation confirms the sensor’s effectiveness in identifying metal debris. The experiment realized the identification of iron debris with a diameter of 93.5 μm and copper debris with a diameter of 447.3 μm under the 3 mm pipe radius, providing a reference for the design of four-coil inductive debris sensor.

High-Frequency Models of Inductive Sensors for Recording Partial Discharges in Electrical-Equipment Insulation

High-Frequency Models of Inductive Sensors for Recording Partial Discharges in Electrical-Equipment Insulation

Recommendation Machine for Avoiding Health and Environmental Hazards by Segregating Medical Wastes – A Survey

Abstract: A growing amount of medical waste needs to be physically segregated. We are recommending a medical waste segregation device for it. The primary goal of this project is to suggest the segregation of waste in municipal offices of India, where the majority of debris is separated using rag pickers which primarily separate the trash from hospitals, which are harmful and dangerous containers made up of toxic metals, by hand. Unfavourable linger leads to health properties such as tuberculosis, tumour, and poisoning metals, which may result in a lower standard of living, decreased longevity, and other side effects. An automated medical waste segregation device is being offered to solve this issue. In medical facilities like hospitals and clinics, this is helpful. India generates 62 million metric tons of waste each year, of which 45 million are disposed of in ways that are dangerous to the environment and human health. Waste management must be effective in intelligent cities. The study proposes an Internet of Things (IoT)-based garbage system that separates waste from various streams, including wet and dry, plastic, paper, metal, and glass. Establish a management system that will improve the chances of recovery and subsequent recycling. The process is simple to control because the system uses an Arduino microcontroller. This separation system's phases include an infrared sensor, an inductive proximity sensor, a raindrop sensor, a photoelectric sensor, and a separation bin. The sensor on each piece of waste detects it and directs it to a specific container for additional processing. The isolated data status will be available in the cloud for monitoring and management

Wear debris measurement in lubricating oil based on inductive method: A review

Almost all of the wear debris generated during the operation of the machine is suspended in the circulating lubricating oil. The analysis of the wear debris in the lubricating oil can effectively monitor the wear state of the machine and provide early warning of failures. An overview on inductive sensors for measuring wear debris in lubrication is introduced. To begin with, the significance of analyzing the wear debris in lubricating oil is explained and the working principle of the inductive wear sensors is illustrated. Furthermore, the development of inductive wear sensors and the key limitations are summarized. Finally, some rest factors affecting the sensor and the processing method of the induction signal aliasing are discussed, and the future development trend is prospected. It is pointed out that developing high sensitivity wear debris inductive sensors, increasing sensor throughput, and solving the problem of aliasing of detection signals are the following issues that should be further studied in the future.

On the Investigation of Frequency Characteristics of a Novel Inductive Debris Sensor.

Lubricants have the ability to reduce frictions, prevent wear, convey metal debris particles and increase the efficiency of heat transfer; therefore, they have been widely used in mechanical systems. To assess the safety and reliability of the machine under operational conditions, the development of inductive debris sensors for the online monitoring of debris particles in lubricants has received more attention from researchers. To achieve a high-precision, high-efficiency sensor for accurate prediction on the degree of wear, the equivalent circuit model of the sensor coil has been established, and its equations discovering the relationship between the induced voltage and excitation frequency have been derived. Furthermore, the influence of excitation frequencies and metal debris on the magnetic flux density has been analyzed throughout the simulations to determine the sensor magnetic field. In order to identify a frequency range suitable for detecting both ferrous and non-ferrous materials with a high level of sensitivity, the analytical analysis and experiments have been conducted to investigate the frequency characteristics of the developed inductive debris sensor prototype and its improved inspection capability. Moreover, the developed inductive debris sensor with the noticeable frequency characteristics has been assessed and its theoretical model has been also validated throughout experimental tests. Results have shown that the detection sensitivity of non-ferrous debris by the developed sensor increases with the excitation frequency in the range of 50 kHz to 250 kHz, while more complex results for the detection of ferrous debris have been observed. The detection sensitivity decreases as the excitation frequency increases from 50 kHz to 300 kHz, and then increases with the excitation frequency from 300 kHz to 370 kHz. This leads to the effective selection of the excitation frequency in the process of inspection. In summary, the investigation into the frequency characteristics of the proposed novel inductive debris sensor has enabled its broad applications and also provided a theoretical basis and valuable insights into the development of inductive debris sensors with improved detection sensitivity.