Photoelectric Sensor Research Articles

An enzyme-free glucose sensing device based on TiO2 nanorod array photoelectric catalysis

A simple one-step hydrothermal method is used to prepare an enzyme-free photoelectric combined glucose sensor based on TiO2NRs/FTO with low cost, sample two-electrode, and excellent detection. Under 380 nm light (0.5 mW cm−2) irradiation and a positive voltage, holes are accumulated on TiO2NRs surface, catalyzing glucose and forming a photocurrent without the need for an enzyme, such as Glucose oxidase (GOx). The designed sensor exhibits high sensitivity (about 0.96 μA mM−1 cm−2, without GOx) and excellent linear relationship in the glucose concentration range of 5–15 mML−1. The prepared glucose sensor performs better with a sensitivity of 1.48 μA mM−1 cm−2 when a certain amount of GOx is mixed in the detected solution. In addition, the sensor has excellent anti-interference resistance to non-reducing chitosan and reducing ascorbic acid with short response time (less than 5 s); thus, it can be used in quick detection with a double electrode system. This sensing device has the advantages of simple fabrication, easy storage, and reusability; therefore, it can be very promising in the portable and rapid monitoring of human blood glucose levels.

Magnetic Levitation Belt Conveyor Control System Based on Multi-Sensor Fusion

Belt conveyors are critical in coal transportation systems; however, they are supported by rollers, which incur high energy costs. Magnetic levitation support is adopted. The measurement of a magnetic levitation air gap is important, and a displacement sensor is usually used in real-time. To address the problems of poor linearity and low measurement stability of single displacement sensors in magnetic levitation systems, a magnetic levitation support system based on multi-sensor data fusion is proposed. First, an industrial camera sensor is used to collect images, and the suspended air gap is obtained through image processing. Second, using an extended Kalman filter, the photoelectric position sensor and industrial camera sensor are fused to the suspension air gap value in the process of suspension. The electromagnet current is controlled by the PID (proportion integration differentiation) control algorithm, and experiments are carried out. Experimental results showed that, compared with an estimation of the suspension state of two sensors before and after EKF fusion, the root mean square error is reduced by 0.0597 and 0.0081, respectively, compared with the measurement value of a single sensor. Moreover, the fusion data were more robust, thereby meeting the requirements of magnetic levitation control.

Experimental investigation on the shock wave and spontaneous ignition of high-pressure hydrogen released into a tube through different narrowness inlets

Due to the high probability of hydrogen leaking from narrow cracks of the vessels, an experimental study is conducted to investigate the spontaneous ignition of high-pressure hydrogen released into a tube through inlets with different narrowness, including circular, square (length-width ratio χ = 1), and two slit shapes of χ = 2 and 3, with the same area. Pressure transducers and photoelectric sensors are used to detect shock wave dynamic variation and ignition occurrence. The results indicate that narrow inlets weaken the shock wave intensity and speed, and the weakening effect increases with narrowness. Moreover, spontaneous ignition is affected. The minimum burst pressure required for spontaneous ignition is higher in the cases with square and slit inlets. Most significantly, when χ is 3, it is 2.5 times that of circular inlet. Meanwhile, for narrow inlets, the ignition flame intensity and speed are enhanced, and the inlet of χ = 2 has the greatest impact.

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.

Two-phase switched reluctance motor drive control system design

The two-phase switching reluctance motor drive control system uses STM8S003F3 as the control chip to realize the control function. The hardware circuit is mainly composed of switched reluctance motor controller power and relay control circuit based on an asymmetric half-bridge circuit, a drive circuit module based on IR2101S, a rotor detection module based on a photoelectric sensor, current detection and protection circuit based on Hall current sensor, power supply circuit based on the multi-integrated chip. The control system has been significantly improved in safety and reliability.

Research Progress on Chiral Supramolecular Sensors for Enantiomer Detection

Chiral substances occur naturally in abiotic and living systems. The recognition and detection of chiral substances in the natural environment or their analysis and detection in biological systems are crucial. Chiral recognition is a research hotspot in clinical medicine, pharmacology, biochemistry, and other fields. Indeed, many researchers have developed various sensors with different functionalized materials for detecting and analyzing enantiomers. Supramolecular systems have important applications in the development of molecular recognition technologies, and the development of supramolecular chemistry is closely related to research on molecular devices. Therefore, this review summarizes the principle of chiral supramolecular sensors for the detection of enantiomers from the perspective of various sensor types, including optical, electrochemical, electrochemical luminescence, photoelectric, and supramolecular chemical sensors. This review also summarizes the relevant reports on chiral supramolecular sensors in the last five years. Finally, we highlight the prospects of supramolecular chiral sensors in future research.

Recognition of DC01 Mild Steel Laser Welding Penetration Status Based on Photoelectric Signal and Neural Network

Achieving online inspection and recognition of laser welding quality is essential for intelligent industrial manufacturing. The weld penetration status is an important indicator for assessing the welding quality, and the optical signal is the most common changing feature in the laser welding process. This paper proposes a new method based on a photoelectric signal and neural network for laser welding penetration status identification. A laser welding experimental system platform based on a photoelectric sensor is built, the laser welding experimental material is DC01 mild steel, and the photoelectric signal in the laser welding process is collected. The collected signal is then processed, and features are extracted using wavelet packet transform and probability density analyses. The mapping relationship between the signal features and weld penetration status is investigated. A deep learning convolutional neural network (CNN)-based weld penetration status recognition model is constructed, with multiple eigenvalue vectors as input, and the model training and recognition results are analyzed and compared. The experimental results show that the photoelectric signal features are highly correlated with the weld penetration status, and the constructed CNN weld penetration status recognition model has an accuracy of up to 98.5% on the test set, demonstrating excellent performance in identifying the quality of the laser welding. This study provides the basis for the online inspection and intelligent identification of laser welding quality.

Polyacrylic acid/polyethylene glycol hybrid antifouling interface for photoelectrochemical immunosensing of CYFRA 21-1 based on TiO2/PpIX/Ag@Cu2O composite

A photoelectrochemical (PEC) transducer based on composite TiO2/PpIX/Ag@Cu2O was prepared for the detection of CYFRA 21–1. TiO2 nanomaterials were synthesized by hydrothermal method. TiO2/PpIX/Ag@Cu2O composites were obtained by combining protoporphyrin Ⅸ (PpIX) molecules and Ag@Cu2O on TiO2. This composite material has strong absorption in visible light region and excellent photoelectric chemical properties. Ascorbic acid (AA) is a good electron donor, which can remove photogenerated holes in liquid environment to inhibit the recombination of photogenerated electrons and hole pairs, thus enhancing the photocurrent and improving its stability. The results showed that the sensor can quantitatively test CYFRA 21–1 in the range of 0.1 pg/mL∼100 ng/mL. The photoelectric chemical sensor has the advantages of high sensitivity, low detection line limit and wide linear range.

Double broadband enhanced absorber based on graphene-coupled metal disk resonator structure

A double broadband terahertz absorber based on nonstructured graphene with a dielectric coupled gold disk structure was investigated in this paper. The results show that one absorption band can be switched from reflection state (“OFF”) to absorption state (“ON”), and the other absorption band can be switched from reflection state (“OFF”) to absorption state (“ON”), with bandwidths of over 90% absorption ranging from 0.46 to 1.4 THz and 2.38 to 3.35 THz, respectively. Furthermore, the double broadband terahertz absorber has polarization and background refractive index insensitivity. The Fabry Perot resonance between the graphene sheet and the bottom gold reflector is primarily responsible for the double broadband absorption in graphene, which can be enhanced by the addition of a gold disk resonator. Because of the aforementioned properties, the proposed absorber has potential applications in multiple optical switches, terahertz photoelectric detectors, modulators, and sensors.

Review on bacteriorhodopsin-based self-powered bio-photoelectric sensors

Bacteriorhodopsin, as a natural biological material with a photoelectric conversion effect, has been attracting researchers’ attention, and quantitative studies have been proceeding in bioelectronics. This work affords a review of bacteriorhodopsin in a specific field of self-powered bio-photoelectric sensors and divides them into three types: energy harvesting devices, biological photoelectric sensors, and special applications. The aim of these devices is to improve the energy conversion efficiency, to realize photoelectric waveform change or to generate optical storage by the intermediate state of the photocycle, respectively. Eventually, it demonstrates the great potential of bacteriorhodopsin in self-powered bio-photoelectric sensors, summarizes some commonly used research methods and means, and finally proposes existing concerns and potential improvements in the future.

Design of High-Precision Infrared Photoelectric Sensor and Its Adoption in Soft Package Counting Management in Workshop

As an imperative part of information technology, photoelectric information technology is widely applied in smart phones, mobile computers, portable electronic products, medical care, and industrial technology. In this research, a high-precision infrared photoelectric sensor is designed, which utilizes XDU3093 chip as a built-in photoelectric sensor. The chip has the characteristics of high-power supply rejection ratio and temperature compensation. Then, the focus is on the design of infrared driving module and infrared detection module. Among them, the pulse current of the infrared drive module is more than 100 mA, and the output current is in the form of square wave. To control noise, an isolation circuit between the infrared drive and other modules is set. Infrared detection involves photoelectric sensor. The nwell diode in CMOS process is utilized as photosensitive diode, and at the same time, the surface of the diode is coated to ensure that only infrared light can generate photocurrent through coating. In the experiment, the infrared driver is simulated, and the results show that the driver module can effectively amplify the collected infrared signals, and the detection accuracy reaches 0.2 V. The simulation of infrared detection suggests that there is a linear relationship between photocurrent and background infrared illumination, and the photocurrent decreases with the increase of distance. The designed infrared photoelectric sensor is applied in the soft package counting link of workshop management. The infrared photoelectric acquisition signal is converted into an analog voltage signal, which is processed by the voltage conversion circuit and then transferred to the single chip microcomputer and software module. After the data is uploaded to the upper computer through the serial port, it shows that the number of soft packages can be accurately identified in the workshop soft package counting link based on the designed infrared photoelectric sensor.

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

Synthesis of WSe2 concentric nanotriangles for fully recoverable photoelectric gas sensors

Transition metal dichalcogenides (TMDs) have a broad prospect in gas sensors due to their vulnerable sensitivity to gaseous species at room temperature (RT). However, the sensors based on TMDs currently still suffer from the low response and incomplete recovery. Herein, we report an unusual synthesis of WSe2 concentric nanotriangles grown by chemical vapor deposition (CVD) and their application to highly sensitive sensors. The WSe2 sensor shows high response to NO2 and triethylamine (TEA) at RT due to the increased active sites from the concentric nanotriangle structure. Under ultraviolet (UV) illumination the gas sensing performance was further improved, including higher response, complete recovery and ppb-level detection limit. This work shed some light in engineering TMDs nanostructures to achieve improved sensor applications.

Simulated Studies of Polarization-Selectivity Multi-Band Perfect Absorber Based on Elliptical Metamaterial with Filtering and Sensing Effect

In this work, the Ag-SiO2-Ag metamaterial with elliptical nano-slits was proposed to investigate the multi-band polarization-dependent perfect absorber. It was found that multi-band perfect absorptions can be induced under TE and TM-polarized illuminations. Simulation results showed that the absorption peaks for TE-polarized wave appeared at 337.6 THz and 360.0 THz with 98.5% and 97.6% absorbance, respectively. Conversely, the absorption peaks for TM-polarized wave appeared at 325.7 THz and 366.1 THz with 96.3% and 97.9% absorbance, respectively. As a result, the elliptical metamaterial presented polarization-selectivity property for perfect absorption, and so, the metamaterial can filter out different frequencies of TE- and TM-reflected waves, i.e., the elliptical metamaterial can be used as a reflecting filter. In addition, this work studied the sensing performance of the elliptical metamaterial and showed that the dual-band sensing performances were different at low and high frequencies. The sensitivities (S) to the refractive index reached up to 151.1 THz/RIU and 120.8 THz/RIU for the TE and TM-polarized waves around 337.6 THz and 325.7 THz, which provide promising potential in near-infrared photoelectric sensor and detector. However, both the absorption frequency and intensity of TM-polarized wave were insensitive to the refractive index of the medium around 366.1 THz, and so, the study provides a theoretical basis for infrared stealth of different media.

Detection of Flying Metal Bodies Based on Photoelectric Composite Sensing.

In order to reduce the impact of the environment on the accuracy and sensitivity of detection, and to meet the requirements of concealment from detection and being lightweight, a technology for detecting flying metal objects based on photoelectric composite sensors is proposed. The method first analyzes the target's characteristics and detection environment, and then compares and analyzes the methods for detecting typical flying metal objects. On the basis of the traditional eddy current model, the photoelectric composite detection model that meets the requirements of detecting flying metal objects was studied and designed. For the problems of the short detection distance and the long response time of the traditional eddy current model, the performance of the eddy current sensor was improved to meet the requirements of detection through optimizing the detection circuit and coil parameter model. Meanwhile, to meet the goal of being lightweight, an infrared detection array model applicable to flying metal bodies was designed, and simulation experiments of composite detection based on the model were conducted. The results show that the flying metal body detection model based on photoelectric composite sensors met the requirements of distance and response time for detecting flying metal bodies and may provide an avenue for exploring the composite detection of flying metal bodies.

Study on wearable pregnancy diagnosis device for rabbits based on photoelectric sensor

Pregnancy diagnosis is essential for rabbits' reproductive management, which allows for re-insemination, and reduces the laboring interval in commercial operations. This study aimed to develop a wearable, non-invasive pregnancy identification device for rabbits. A sensing probe contained three LEDs (Light wavelength is 660 nm, 850 nm, and 930 nm respectively), two Si-based photodiodes, and a host with signal processing was developed. Room-temperature-vulcanized (RTV) silicone rubber, aluminum oxide powder, and dyes of different colors were used to make the abdominal tissue phantom of pregnant female rabbits (PRs) and non-pregnant female rabbits (NPRs) to test the sampling stability of the developed device. The results showed that the variation coefficient of the sampling data of the device was<0.013, and the stability met the use requirements. Sampling data from 419 female rabbits were used to build partial least squares discrimination analysis (PLS-DA) and support vector machine (SVM) models of different abdominal hair densities, including dense hair, sparse hair, hair removal, and hair mixing. The classification results of the two models showed that SVM had the best performance, the Ac, Re, Pre, and F-score are more than 80%, respectively. Then, the trained SVM model was then used as the identification model and downloaded to the developed device. Another 218 rabbits were used to verify the performance of the developed device, and the prediction performance was the best among the hair removal rabbits, with Ac, Re, Pre, and F-socre of 83.94%, 83.67%, 81.19%, and 82.41% respectively. The results show that the wearable device developed in this study has a good prediction performance for rabbits with abdominal hair removal, and provides a new idea for pregnancy diagnosis of rabbits.

Pd/ZnS/ZnO sensitive selective detection photoelectrochemical sensor for the detection of Cd2+

A sensitive photoelectrochemical method for the detection of Cd2+ ions was realized using Pd/ZnS/ZnO nanoparticle modified electrodes. The ZnS/ZnO bilayer material was prepared by hydrothermal method using nickel foam as the substrate then the three-layer nanomaterial photoelectric sensor was prepared using pulse plating method. Then, a series of electrochemical and photoelectrochemical tests were conducted to measure the electrochemical and photoelectrochemical properties. The test results show that the composite electrode has good electronic conductivity, improved photosensitivity, and a detection response range of 0.1 μM–100 μM for Cd2+ with good sensitivity and selectivity and lower detection limit compared with the conventional Cd2+ sensor.

Flexible Photoelectric Pulse Detection Sensor and Image Processing of Detection Signal

Biomedical sensors can detect all kinds of human life information. The pulse signal is one of the most important physiological parameters of the human body. An ultra-thin and flexible photoelectric pulse detection sensor is built, a pulse detection system based on the sensor circuit is built, and the image processing of the detected pulse signal is carried out. Oleic acid is used to modify the organic semiconductor layer of the phototransistor. Silver nanoparticles (AgNCs) are also infiltrated into organic semiconductor materials to form nanocomposites. The hardware circuit includes signal amplification, baseline correction, 50 Hz notch filter, and band-pass filter. In the experiment, the prepared nanocomposites are analyzed for photoelectric properties. The results show that the transfer curve of the device is bipolar without illumination, and the hole transport characteristics are more obvious than the electron transport characteristics. The hole mobility is 0.06 mm2/V/S, and the electron mobility is 1.34×10−4 cm2/V/S. Hole mobility greater than electron mobility can effectively improve photoconductivity gain. The detection of different working voltages shows that the pulse wave detected by the prepared sensor has obvious P, T, and D waves. The image processing technology is used. After the output pulse signal image passes through the notch and low-pass filters, the pulse signal’s high-frequency interference is suppressed. After envelope filtering, the signal frequency amplitude of the pulse signal decreases (from 400 mV–700 mV to −150 mV~150 mV). Then, the baseline drift is effectively removed.

All-Silicon Photoelectric Biosensor on Chip Based on Silicon Nitride Waveguide with Low Loss.

Compared to the widely used compound semiconductor photoelectric sensors, all-silicon photoelectric sensors have the advantage of easy mass production because they are compatible with the complementary metal-oxide-semiconductor (CMOS) fabrication technique. In this paper, we propose an all-silicon photoelectric biosensor with a simple process and that is integrated, miniature, and with low loss. This biosensor is based on monolithic integration technology, and its light source is a PN junction cascaded polysilicon nanostructure. The detection device utilizes a simple refractive index sensing method. According to our simulation, when the refractive index of the detected material is more than 1.52, evanescent wave intensity decreases with the growth of the refractive index. Thus, refractive index sensing can be achieved. Moreover, it was also shown that, compared to a slab waveguide, the embedded waveguide designed in this paper has a lower loss. With these features, our all-silicon photoelectric biosensor (ASPB) demonstrates its potential in the application of handheld biosensors.

Evaluation of a Real-Time Monitoring and Management System of Soybean Precision Seed Metering Devices

Aiming at precise evaluation of the performance of soybean seed metering devices, a photoelectric sensor-based real-time monitoring system was designed. The proposed system mainly included a photoelectric sensor module for seeding signal collecting, Hall sensors speeding module, microcontroller unit (MCU), light and sound alarm module, human–machine interface (HMI), and other parts. The indexes of miss, multiples, flow rate, and application rate were estimated on the basis of seeder speed, seed metering disk rotation rate, photoelectric sensor signals, and clock signals. These real-time statistics of the seeding process were recorded by seeding management system. The laboratory results showed that the detection errors of seeding quantity of both big- and small-diameter soybeans were less than 2.0%. Miss and multiples index estimated by this system were 0.4% and 0.5% than that of seeding image monitoring platform (SIMP), respectively. In field tests, miss and multiples index can be used to evaluate the performance of seed metering device, and big-diameter seeds can be detected more precisely than small ones by these photoelectric sensors. This system can provide support for evaluation of working performance of seed metering devices and have a positive effect on seeding monitoring technology.