Flow Sensor System Research Articles

Vehicle flow indication and identification using FBG sensors

Abstract This paper proposes a vehicle flow monitoring system utilizing fiber Bragg grating (FBG) sensor technology. The system comprises a prototype road model along with a car with varying loads. The FBG sensor is embedded in the road surface for sensing the strain induced by the vehicle movement. The laboratory experiments were conducted using an embankment model equipped with FBG sensor to identify vehicle movement under static and movable loads. Under static condition, different loads were applied on the car and the corresponding wavelength shifts have been measured using FBG-interrogator. Under dynamic condition, the vehicle was moved with certain speed and the corresponding wavelength shifts were recorded over time. The sensitivity of FBG for vehicle load sensing has been obtained as 0.3 pm/N. The proposed vehicle flow sensor system offers good accuracy and sensitivity and has potential applications for real-time vehicle flow monitoring. The proposed sensor system can be used to analyze road surface irregularities, crucial for assessing heavy-vehicle fatigue.

Hybrid System PSO-ANFIS for Optimization of The Water Level in The Tank

The speed and pressure of the water flow are determined by the height and volume of the water. The speed of the water flow in the actuator is determined by the use of this flow sensor system. A good tank-based water flow control model should be developed. At a certain point, the actuator stabilizes the rate of water production per minute. Therefore, it is necessary to develop an automatic and precise control technique. Many Artificial Intelligence (AI) methods are used in system optimization. Among them are Particle Swarm Optimization (PSO), Neural Network (NN), Fuzzy Inference System (FIS), and ANFIS. Adaptive Neuro Fuzzy Inference System (ANFIS) is a combination of NN and FIS. In this study, the PSO method was combined with ANFIS. This hybrid method produces better optimization compared to the previous method. The best water level control simulation results are PSO-ANFIS with an overshot of 0.572 pu, undershot of 0.563 pu, and flow output overshot of 0.008 pu, undershot of 0.009 pu.

Stability of Water Flow in Tanks Using Particle Swarm Optimization (PSO) Method

The stability of the speed and pressure of the water flow is determined by the height and volume of the water. The speed of water flow in the actuator is determined by the use of this flow sensor system. A good tank-based water flow control model must be developed. At a certain point, the actuator stabilizes the water production rate per minute. Therefore, it is necessary to develop automatic and precise control techniques. Many Artificial Intelligence (AI) methods are used in system optimization. Among them are the Firefly Algorithm (FA) and Particle Swarm Optimization (PSO). In this research, conventional methods, Auto tuning methods, and PSO methods are used. The PSO method produces better optimization compared to the previous method. The water flow stability indicator in this simulation is shown by the size of the overshot and undershot values for each method. The best water level control simulation results are the PSO method with the smallest overshot value of 0.0333 pu, the smallest undershot value of 0.0347 pu, and the output flow results have the smallest overshot value of 0.0013 pu, the smallest undershot value of 0.0011 pu.

Monolithic Integration of Ultraslim Flow Sensor and Medical Guidewire by Laser Filament Scanning Sintering for In Vivo Diagnostics of Cardiovascular Diseases.

In this study, an ultraslim thermal flow sensor system integrated onto a 340 μm diameter medical guidewire was developed using a laser filament scanning sintering method for the early diagnosis of cardiovascular diseases. The proposed system is a calorimetric-based micro thermal flow sensor comprising a microheater and two thermistors. Prior to fabrication, the sensor design was optimized through flow simulation, and the patterned sensor was successfully implemented on a thin and curved surface of the medical guidewire using a laser patterning method with Ag nanoparticles. The performance of the ultraslim thermal flow sensor-on-guidewire system (SoW) was evaluated under pulsatile flow by using an artificial heartbeat simulator with differentially induced fluid flow velocities of up to 60 cm/s. The resulting electrical signals generated by the temperature difference between the two thermistors caused by the fluid flow were measured across different velocity ranges. Based on the obtained data, a calibration curve was derived to establish the relationship between the fluid velocity and the sensor output voltage. Furthermore, the SoW was tested on living animals, whereby the measured blood flow velocities were 60-90 cm/s in the left coronary artery of pigs. This research demonstrates the potential of ultraslim microsensors, such as the developed thermal flow sensor system, for various industries, particularly in the medical field.

A Reliability Analysis of a MEMS Flow Sensor with an Accelerated Degradation Test.

With the wide application of flow sensors, their reliability under extreme conditions has become a concern in recent years. The reliability of a Micro Electro Mechanical Systems (MEMS) flow sensor under temperature (Ts) is researched in this paper. This flow sensor consists of two parts, a sensor chip and a signal-processing system (SPS). Firstly, the step-stress accelerated degradation test (SSADT) is implemented. The sensor chip and the flow sensor system are tested. The results show that the biggest drift is 3.15% for sensor chips under 150 °C testing conditions, while 32.91% is recorded for the flowmeters. So, the attenuation of the SPS is significant to the degeneration of this flowmeter. The minimum drift of the SPS accounts for 82.01% of this flowmeter. Secondly, using the Coffin-Manson model, the relationship between the cycle index and Ts is established. The lifetime with a different Ts is estimated using the Arrhenius model. In addition, Weibull distribution (WD) is applied to evaluate the lifetime distribution. Finally, the reliability function of the WD is demonstrated, and the survival rate within one year is 87.69% under 85 °C conditions. With the application of accelerated degradation testing (ADT), the acquired results are innovative and original. This research illustrates the reliability research, which provides a relational database for the application of this flow sensor.

Development of an Automatic Water Flow Sensor System Using ESP32 for Efficient Water Control

Access to clean and reliable drinking water is essential for human well-being. This research aims to develop an automatic water flow sensor system based on ESP32 microcontroller for efficient water control. The study employs the Development (Observation) method to observe and record the activities involved in the system development process. The system allows users to adjust the water discharge according to their requirements by utilizing a keypad interface and modifying the Arduino IDE code. The experimental results demonstrate a high accuracy of 92% with an 8% error rate, indicating the system’s reliability in controlling the water flow. Moreover, stabilizing the ESP32 microcontroller by providing a voltage of at least 5V ensures optimal performance. The findings suggest the practicality and cost-effectiveness of the developed system, which can contribute to improving water management and conservation efforts worldwide.

Wireless Stent Flow Sensor System for the Evaluation of Breathing Airflow in the Airway of Experimental Animals

Wireless Stent Flow Sensor System for the Evaluation of Breathing Airflow in the Airway of Experimental Animals

Enhanced water flow sensing performance based on multi-ciliated structure of ionic polymer–metal composite

Ionic polymer–metal composite (IPMC) is a promising candidate for underwater sensing due to the merits of rapid response, flexibility, miniaturization, and self-powered nature. The high sensitivity of a sensor is vital for underwater robots. Inspired by the lateral line cilia of fish, a new water flow sensor system based on the multi-ciliated structure of the IPMC is presented to improve the sensitivity of the sensor. As illustrated by the experiments on oscillatory flow, the sensitivity and detection range of the multi-ciliated sensor reached 3.83 times and increased by about 39%, respectively, compared with that of a single sensor. In addition, an array composed of multi-ciliated systems of IPMCs was successfully applied to the location of a vibrating dipole, while the velocity prediction of underwater moving objects was also realized with a minimum average error rate of 1.70%. The system with high sensitivity proposed in this paper is promising to be an effective supplement to traditional underwater detection methods.

Two-Dimensional CMOS MEMS Thermal Flow Sensor With High Sensitivity and Improved Accuracy

In this paper, we report a two-dimensional (2D) Thermoresistive Micro Calorimetric Flow (TMCF) sensor by using a $0.35~\mu \text{m}$ 2P4M CMOS MEMS technology. For the airflow, the fabricated and the open-space packaged 2D flow sensor system achieved the highest normalized sensitivity of 32 mV/W/(m/s) with respect to input heating power and gain. To overcome the sensor output drifting issue due to the locally redistributed fluid flow near the bonding wires, a digital signal conditioning algorithm using the inverse distance weighting (IDW) method, instead of the conventional fitting method with sine and cosine function, was proposed. Accordingly, the calibrated 2D flow sensor showed an improved velocity accuracy of ±4% and the angle accuracy of ±3° for an input airflow from 0 to 20 m/s. Therefore, the developed highly sensitive 2D TMCF sensor will be a promising device for the airflow measurement in the smart buildings and the meteorological monitoring system. [2019-0259]

A Smart Dual-Mode Calorimetric Flow Sensor

A smart thermal flow sensor system is presented. It makes use of a novel heater control circuit, which can automatically set the operating mode to either constant power or constant temperature difference. It overcomes the limitations of single-mode thermal flow sensors, such as temperature overshoots at low flow rates at constant power mode, or excessive power consumption at high flow rates at constant temperature difference mode. The system is especially useful for temperature sensitive and portable applications, such as respiratory monitoring for medical diagnostics. In this article, a detailed description of the sensor’s design, implementation, and experimental validation are presented. The proposed dual-mode flow sensor achieves an overtemperature reduction up to 9.5% compared with thermal flow sensors operating in constant power mode alone, and a power reduction up to 13.6% compared with thermal flow sensors operating in constant temperature difference mode alone for the flow range of 0 to 50 slm while offering an improved overall sensitivity.

MEMS Flow Sensor System with Tracheal Tube Device for Evaluation of Respiration and Heartbeat Signal by Detecting Airflow at Mouth of Infant

MEMS Flow Sensor System with Tracheal Tube Device for Evaluation of Respiration and Heartbeat Signal by Detecting Airflow at Mouth of Infant

Stretchable, Implantable, Nanostructured Flow-Diverter System for Quantification of Intra-aneurysmal Hemodynamics.

Random weakening of an intracranial blood vessel results in abnormal blood flow into an aneurysmal sac. Recent advancements show that an implantable flow diverter, integrated with a medical stent, enables a highly effective treatment of cerebral aneurysms by guiding blood flow into the normal vessel path. None of such treatment systems, however, offers post-treatment monitoring to assess the progress of sac occlusion. Therefore, physicians rely heavily on either angiography or magnetic resonance imaging. Both methods require a dedicated facility with sophisticated equipment settings and time-consuming, cumbersome procedures. In this paper, we introduce an implantable, stretchable, nanostructured flow-sensor system for quantification of intra-aneurysmal hemodynamics. The open-mesh membrane device is capable of effective implantation in complex neurovascular vessels with extreme stretchability (500% radial stretching) and bendability (180° with 0.75 mm radius of curvature) for monitoring of the treatment progress. A collection of quantitative mechanics, fluid dynamics, and experimental studies establish the fundamental aspects of design criteria for a highly compliant, implantable device. Hemocompatibility study using fresh ovine blood captures the device feasibility for long-term insertion in a blood vessel, showing less platelet deposition compared to that in existing implantable materials. In vitro demonstrations of three types of flow sensors show quantification of intra-aneurysmal blood flow in a pig aorta and the capability of observation of aneurysm treatment with a great sensitivity (detection limit as small as 0.032 m/s). Overall, this work describes a mechanically soft flow-diverter system that offers an effective treatment of aneurysms with an active monitoring of intra-aneurysmal hemodynamics.

Evaluation of the Approaches of the Anaesthesiologists on Maintenance of Anaesthesia Machines.

In this study, we aimed to discuss the level of knowledge and approach on 'maintenance, calibration and cleaning of anaesthesia devices' among anaesthesiologists in Turkey. A questionnaire was prepared with 21 questions based on the Google document system, and these questionnaires were sent to the anaesthesiologists via e-mail. Overall, 226 anaesthesiologists answered our survey. With respect to the maintenance and calibration, anaesthesiologists had sufficient information about the vaporizer and the carbon dioxide canister devices; however, information about the vital components, such as disassembly of the anaesthesia machine, flow sensor, oxygen sensor, battery and exhaust system, was insufficient. The cleaning and sterilization procedures were performed when the devices became dirty, and the bacteria filter was used only for the protection of the anaesthesia system. There was a lack of knowledge about how and which part of the anaesthesia device should be disinfected. In total, 85% of the survey participants were thinking of the need of additional education on anaesthesia machine maintenance. It is observed that education about anaesthesia device maintenance, calibration and cleaning issues is obviously necessary for the anaesthesiology specialists in our country. We believe that it would be useful to highlight this issue to anaesthesia educational institutions and anaesthesia associations.

Afocal optical flow sensor for reducing vertical height sensitivity in indoor robot localization and navigation.

This paper introduces a novel afocal optical flow sensor (OFS) system for odometry estimation in indoor robotic navigation. The OFS used in computer optical mouse has been adopted for mobile robots because it is not affected by wheel slippage. Vertical height variance is thought to be a dominant factor in systematic error when estimating moving distances in mobile robots driving on uneven surfaces. We propose an approach to mitigate this error by using an afocal (infinite effective focal length) system. We conducted experiments in a linear guide on carpet and three other materials with varying sensor heights from 30 to 50 mm and a moving distance of 80 cm. The same experiments were repeated 10 times. For the proposed afocal OFS module, a 1 mm change in sensor height induces a 0.1% systematic error; for comparison, the error for a conventional fixed-focal-length OFS module is 14.7%. Finally, the proposed afocal OFS module was installed on a mobile robot and tested 10 times on a carpet for distances of 1 m. The average distance estimation error and standard deviation are 0.02% and 17.6%, respectively, whereas those for a conventional OFS module are 4.09% and 25.7%, respectively.

Silicon Thermal Flow Sensor Based on Ceramic Substrate

A silicon thermal flow-sensor system based on ceramic substrate is described in this paper. The sensor chip is mounted on a ceramic substrate with a metal heat sink. The simulation by ANSYS software and the experiment are done for determining suitable package size. The results from the ANSYS simulation and the standard flow test in the flow tunnel show that when the radius of the ceramic is 10mm and the heat conduction is35Wm-1K-1, the performance of the sensor is much better. The heat sink will make the flow-sensor more stable. The wind speed up to 35m/s and the precision of 0.5m/s are acquired in this experiment.

Volumetric mass flow sensor for citrus mechanical harvesting machines

A volume-based mass flow sensor system was developed to estimate the total mass of fruit travelling on the inclined and horizontal conveyors of two citrus mechanical harvesting systems. A LIDAR (light detection and ranging) sensor was used to scan the conveyor cross-sectional area and use the distance related-information to estimate the bulk volume and total mass of fruit on the conveyor by integrating the data over time. A custom algorithm was developed to analyze the data and calculate the fruit volume. Fruit volume was used to estimate the total fruit mass.Sensor system was tested in the laboratory on two different conveyor systems: an inclined conveyor used in a mechanical harvester (conveyor flap height=8cm), and a horizontal conveyor used in a debris removal system (conveyor flap height ⩽3cm). The tested conveyor speeds ranged from 0.59m/s to 1.71m/s. The system performance for the tested speed ranges was an average error of 7% (standard deviation [SD]±7%) and 7% (SD±5%) for the inclined and horizontal conveyors, respectively. The average total fruit mass estimation error during mechanical harvesting was 10% (SD±6%) for 11 field trails that involved scanning 512–1356kg of the fruit on a horizontal conveyor of a debris removal system. Overall, the developed sensor system can be used for volumetric yield monitoring of citrus. The sensor system performance will likely be improved using instant conveyor speed during the estimation of total fruit mass.

Fiber Bragg grating-tuned feedback laser flow sensor system

In this paper, a fiber Bragg grating (FBG) air flow sensor system using an all-fiber feedback laser is proposed. The operating principle of the feedback laser is based on the mode-locking mechanism between a Sagnac loop multi-grid filter and a tunable FBG <!-- no-mfc -->sing<!-- /no-mfc -->le-wavelength filter. A shift in the lasing wavelength is attributed to the change in the heat energy of the coil heater. This is because the flow sensor depends on the variations in the heat energy of the coil heater surrounding the FBG, thereby causing a shift in the Bragg wavelength owing to a thermo-optic effect. In order to investigate the spectral response as a function of the flow speed of air, a simple and cost-effective intensity-based demodulation technique using a micro-optic band-pass filter is demonstrated. The flow sensitivity of the sensor system was 0.7dB/(l/min) within a linear region.

Attitude Control of a Small UAV Using a Flow Sensor System

The present paper describes the attitude control of a small UAV using a flow sensor system. The installed flow sensors measure the flow field characteristics around the wing, which are sensitive to the attitude of the airplane. The dynamics of the responses of the flow sensors to the attitude variation were identified in dynamic wind tunnel experiments, and the obtained dynamic model related the flow sensor output to the airplane attitude. The attitude of an airplane was then controlled by the elevons so that the desired flow sensor output was attained, resulting in a maximum lift coefficient. The controller was designed using the H∞ control method with sufficiently robust stability. Numerical simulations and actual flight tests were conducted, and effective control of the airplane attitude using the small flow sensors was demonstrated.

The debris flow sensor system utilizing steel check dam

The debris flow sensor system utilizing steel check dam

A Flexible Flow Sensor System and Its Characteristics for Fluid Mechanics Measurements

In this paper, we present a novel micromachined hot-film flow sensor system realized by a technique using a film depositing processes and incorporating a standard printed circuit. Sensor electrodes and electronic circuits are preprinted on a flexible substrate of polyimide (PI), i.e., a flexible printed circuit board (FPCB). The sensing element, which is made of Cr/Ni/Pt with a temperature coefficient of resistance around 2,000 ppm/K, is fabricated on the FPCB by either magnetron sputtering technology or pulsed laser deposition (PLD). The sensor can be packed efficiently at high-density and integrated with signal processing circuits without additional pads. A simple fabrication process using mature technique and materials selection guarantees that the time and costs are greatly reduced. Both steady-state and transient characteristics of the sensors are experimentally tested, and the results presented to validate the effectiveness of the sensors.