Speed Measurement System Research Articles

Development of a Shoelace Tensile Testing System and Investigation into the Effects of Different Running Speeds on Shoelace Tensile Variation

AbstractThis study investigated the validity and sensitivity of a custom-made shoelace tensile testing system. The aim was to analyze the distribution pattern of shoelace tension in different positions and under different tightness levels during running. Mechanical tests were conducted using 16 weights, and various statistical analyses, including linear regression, Bland-Altman plots, coefficient of variation, and intraclass correlation coefficient, were performed to assess the system’s validity. Fifteen male amateur runners participated in the study, and three conditions (loose, comfortable, and tight) were measured during an upright stance. The system utilized VICON motion systems, a Kistler force plate, and a Photoelectric gate speed measurement system. Results showed a linear relationship between voltage and load at the three sensors (R2 ≥ 0.9997). Bland-Altman plots demonstrated 95% prediction intervals within ± 1.96SD from zero for all sensors. The average coefficient of variation for each sensor was less than 0.38%. Intraclass correlation coefficient values were larger than 0.999 (p<0.0001) for each sensor. The peak tension of the front shoelace was greater than that of the front and middle when the shoelace was loose and tight. The rear shoelace had the highest tension force. The study also found that shoelace tension varied throughout the gait cycle during running. Overall, this research provides a novel and validated method for measuring shoelace tensile stress, which has implications for developing automatic shoelace fastening systems.

Experimental Study of Hot-Sphere Anemometer Response in Stratospheric Environment.

Accurate wind speed measurement in low-pressure conditions is crucial for the thermal performance validation and attitude control of stratospheric aircraft. As air density decreases, traditional wind speed measurement systems based on principles such as dynamic pressure, heat transfer, ultrasound, and particle velocimetry face significant challenges when applied in low-pressure environments, often failing to achieve the required measurement accuracy. This paper presents the development of a wind speed simulation system based on a rotation method designed to operate in low-pressure conditions, utilizing a space environment simulation chamber in conjunction with a high-precision turntable. The system was employed to conduct response tests on a constant heat flow thermal sphere anemometer within a stratospheric pressure range of 1 kPa to 30 kPa. The experimental results revealed that at extremely low Reynolds numbers, the probe signal exhibited increasing nonlinearity, significantly affecting the response curve at pressures below 15 kPa. While the sensitivity of the hot-sphere probe remained relatively stable at wind speeds above 5 m/s, it decreased nonlinearly as the pressure dropped when wind speeds fell below 5 m/s. Furthermore, this paper analyzes the impact of various interpolation methods on wind speed conversion errors, providing valuable data to support the future development and validation of stratospheric aircraft.

The relationship between functional movement patterns, dynamic balance and ice speed and agility in young elite male ice hockey players.

Understanding the relationship between the functional state of the musculoskeletal system and skating performance in ice hockey players is essential, as it can provide valuable insights for the development of training programs tailored to the specific needs of athletes. This study investigated the relationship between functional movement patterns, dynamic balance, and ice speed and agility in young elite male ice hockey players. The study involved sixty elite male ice hockey players aged 14 to 18 years, with an average age of 15.9 ± 0.85 years and training experience ranging from 7 to 9 years. Functional movement patterns were evaluated using the Functional Movement Screen™ (FMSTM). Dynamic balance was assessed using the lower quarter Y-Balance test (YBT-LQ). Fitness tests on ice were conducted using a professional Smart Speed measurement system. Negative correlations were found between the in-line lunge and the results of the 5-m forward (rho = -0.31, p = 0.018) and 5-m backward (rho = -0.27, p = 0.040), as well as between the hurdle step and the 30-m forward skating test result (rho = -0.26, p = 0.043). Positive correlations were observed between shoulder mobility and both forward (5-m: rho = 0.27, p = 0.035) and backward skating results (5-m: rho = 0.35, p = 0.006; 30-m: rho = 0.26, p = 0.047), and between active straight leg rise and both the 5-m forward skating (rho = 0.38, p = 0.002) and agility tests (rho = 0.39, p = 0.002). The study also revealed positive correlations between the magnitude of asymmetries in the anterior reach distance of the right and left legs and the results of 5-m forward (rho = 0.34, p = 0.009) and backward skating (rho = 0.32, p = 0.013). Additionally, a positive correlation was found between the agility test and the magnitude of asymmetries in the posteromedial reach distance (r = 0.32, p = 0.012) as well as the composite YBT score (r = 0.28, p = 0.031). Negative correlations were found between normalized reach distances in the YBT-LQ and performance outcomes in both forward and backward skating, as well as in the agility test, indicating that greater reach distance corresponds to faster skating. These findings suggest the potential impact of balance and hip mobility on skating speed and agility and emphasize the importance of symmetry for optimal performance among ice hockey players.

Interconnect‐Integrated GaInP/AlGaAs Schottky Photodetector Array with Heterojunction‐Assisted Enhanced Photovoltaic Effect for Automotive Speed Measurement Systems

AbstractReducing power consumption has always been a pressing issue for integrated circuits. Currently, there is a strong interest in the development of self‐powered photodetectors with low power consumption, high quantum efficiency, and high integration. In this work, a novel GaInP/AlGaAs photodetector is developed, where the photovoltaic effect of the Schottky junction is enhanced by the assistance of underneath GaInP/AlGaAs heterojunction, achieving near unity quantum efficiency, high integration, and ultrafast response speed. A single device exhibits a responsivity (R) of 467 mA W−1 in photovoltaic mode, a specific detectivity (D*) of 1.43 × 1011 Jones, a power conversion efficiency (PCE) of 14.5%, and an external quantum efficiency (EQE) of 96.56%. Further, an interconnect integration technique is used to integrate 81 individual detector units onto a 5 × 5 mm2 chip, resulting in a detector array that significantly improves the optical response. The device array has a high frequency feature with a fast response of 19 µs and a −3 dB bandwidth of 21.34 kHz. The interconnect chip is further integrated with a STM32 chip to realize an automotive speed measurement system. This work provides a novel technological solution for a high‐frequency, highly integrated photodetector array using heterojunction‐assisted enhanced GaInP Schottky junctions.

Uncertainty evaluation for wind speed measurement part (1): “GUM method and Monte Carlo method”

Due to the lack of analysis and research on the performance of different uncertainty evaluation methods in the field of wind speed measurement, it is difficult to choose the most favorable uncertainty evaluation method in the specific wind speed measurement, which will affect the efficiency and accuracy of results. In view of the above situation, this study applied three commonly used uncertainty evaluation methods (conventional GUM method, correlation GUM method and MCM method) to the uncertainty evaluation of wind speed measurement, and analyzed the performance of different methods to provide technical support for specific applications. Firstly, taking the pitot tube wind speed measurement system as an example, the principle and model of wind speed measurement are introduced; Secondly, explain the steps and processes of the above three methods for evaluating uncertainty; Finally, taking a 10 m/s wind speed measurement as an example, the above three methods were used (The correlation GUM method incorporates the correlation between wind tunnel stability and uniformity in its evaluation) to evaluate the uncertainty of wind speed measurement in the Pitot tube wind speed measurement system, and the evaluation results were verified and compared accordingly. The following results were obtained:1) The three uncertainty evaluation methods are all applicable to the evaluation of wind speed measurement uncertainty in this field; 2) The accuracy of evaluation results: MCM method > correlation GUM > conventional GUM, among which correlation GUM method effectively improves the accuracy of uncertainty U95 by 23 % compared to conventional GUM method; 3) Evaluation method operability: MCM method > conventional GUM > correlated GUM. Therefore, we suggest that, when evaluating the uncertainty of wind speed measurement, the MCM method should be given priority when there are high requirements for accuracy and operability. When there are difficulties in the use and promotion of MCM, but there is a high requirement for accuracy, the correlation GUM method can be used. When the accuracy requirement is not high and the calculation is not too complicated, the conventional GUM method can be used.

Design of Wind Speed Measurement System in Wind Tunnel Based on Pitot Tube

In the current era, the development of science in all aspects continues to change. The use of wind at this time is necessary for the efficiency of the energy used. The wind speed research method for this study utilizes experimental laboratory methods, specifically employing a Pitot tube measuring instrument to collect wind speed data. From the wind speed data obtained using a frequency of 25–50 Hz, there is only a slight difference between readings from a testometer with a pitot tube and only at frequencies of 39 Hz and 43 Hz, which have a visible difference. The graph indicates that the research was successful by comparing the readings on the testometer.

Wi-Rotate: An Instantaneous Angular Speed Measurement System Using WiFi Signals

We propose the design, implementation, and evaluation of an instantaneous angular speed (IAS) measurement system, namely Wi-Rotate, using commercial-off-the-shelf (COTS) WiFi hardware. Wi-Rotate exploits the Channel State Information (CSI) of WiFi signals to extract the physical characteristics of the rotation object to achieve accurate contact-free IAS measurements. Wi-Rotate contains three main components: Wi-Fresnel model, Wi-Phase model, and a combination model. Wi-Fresnel model explores the signal amplitude variation features when the rotating object cuts the Fresnel zone boundary to track target rotation. Wi-Phase model leverages signal phase variation and formalizes the problem of determining IAS as a linear programming problem. The combination model combines the IAS values obtained by Wi-Fresnel and Wi-Phase and utilizes a clustering method to further improve measurement accuracy. Comprehensive experiments are conducted to demonstrate the advantages of Wi-Rotate in terms of accuracy, sensing range, and system latency. Wi-Rotate is able to achieve real-time rotation measurements at an accuracy higher than 99% when the target is within 2 meters. Even when the target is 3 meters away, Wi-Rotate can still achieve an accuracy of 94%, demonstrating the long-range tracking capability which is critical for industrial applications.

Multi-Sensor Resilient Fusion Estimation for Speed Measurement and Positioning System of Trains Under Cyber Attacks and Physical Faults

Multi-Sensor Resilient Fusion Estimation for Speed Measurement and Positioning System of Trains Under Cyber Attacks and Physical Faults

MEASUREMENT OF LINEAR VELOCITY USING A MOBILE ROBOTIC PLATFORM WITH COMPUTER VISION

This article presents an approach to integrating computer vision algorithms into the control system of traction electric drives in rail transport. It demonstrates the utilization of computer vision algorithms for calculating linear velocity as an alternative to conventional sensors like wheel odometers, GPS, DGPS and inertial sensors, which may prove ineffective on slippery surfaces and at low speeds. As a result, this article focuses on employing linear velocity as feedback within the control system to enhance power efficiency during starting and stopping and to prevent wheel slip. The electric drive control system has been successfully implemented and tested on a robotics platform designed for simulating dynamic behaviors in real rail transports scenarios. The article details the development process of this robotics platform, which is employed to mimic real-world dynamic conditions in rail transport. The proposed control algorithm for speed estimation is assessed using a specially designed test bench, revealing its capability to predict speed with a relatively high degree of accuracy. Additionally, an optical flow algorithm for velocity estimation is introduced and evaluated through a specially designed test rig, indicating a strong correlation between the predicted vehicle speed and the measurements from precision optical encoders. The study also determines the optimal feature window size for real-time optical flow rate estimation. In summary, this approach exhibits significant potential for accurate speed estimation. Ongoing experiments are being conducted under various real-world conditions, with future research aimed at developing a dependable autonomous system for speed measurement. The integration of modern digital computer vision technologies not only enhances the traction characteristics of electric drives but also extends the capabilities of traction electric drives to meet the rigorous demands of industrial equipment.

Design and Development of Fiber Optic Sensor System for Rotational Speed Measurement

Design and Development of Fiber Optic Sensor System for Rotational Speed Measurement

Luminescent Solar Concentrators with Dual Functions of Photovoltaic and Piezoelectric Properties for Wireless Self‐Powered Speed Measurement

AbstractThe solar‐only response nature limits the luminescent solar concentrators (LSCs) to solar harvesting rather than responding to other stimuli, which restricts the role of LSCs to energy supply in self‐powered internet of things (IoT) systems, and the application potential of LSCs in self‐powered devices has been seriously overlooked. In this work, LSCs with photovoltaic and piezoelectric features are proposed for the first time, extending the application scenario of LSCs to self‐powered sensors with pressure responsiveness. The luminescent layer of perovskite‐polymer composite film is prepared via in situ blade coating with the piezoelectric polymer matrix of poly(vinylidenefluoride‐trifluoroethylene) (P(VDF‐TrFE)). P(VDF‐TrFE) possesses stronger DMF adsorption capacity and higher electroactive phase content than a conventional piezoelectric matrix of poly(vinylidene fluoride) (PVDF), which not only reduces the residual‐solvent‐induced defects in perovskite luminophores, but also brings a sensitive pressure response to LSCs. The dual‐functional LSCs achieve a power conversion efficiency of 1.01% and a output piezoelectric voltage of 0.95 V can be obtained even at a low pressure of 0.16 kPa. A self‐powered speed measurement system is demonstrated, and the actual speed measurement is carried out. Such dual‐functional LSCs show great potential in self‐powered electrical devices, which can be applied to low‐energy‐consumption IoT systems and other commercial smart home products.

Proposal for a command structure written in python programming language for implementation on automotive speed sensors test bench

This work presents a programming logic developed within a code written in Python language, guiding engineering teaching. Where with this logic it is possible to command a test bench for a vehicle speed measurement system. This command is made through the amount of rotation of a stepper motor based on frequency values. In addition, the programming logic can be applied to other devices or equipment that contain stepper motors, in order to promote its command through its amount of rotation and acceleration.

Application of Microcontroller in Automobile Engine Speed Measurement System

Since the reform and opening up, China has always upheld the development concept of science and technology, and under the development trend of technology globalization, a large number of foreign automobile engine technology has been gradually introduced into the production and development of China’s automobile industry. In this paper, the author mainly discusses the application of microcontroller and microcontroller in the automobile engine speed measurement system, and will also explain the microcontroller from the perspective of embedded system.

The Honda Automotive Laboratories of Ohio Wind Tunnel

<div class="section abstract"><div class="htmlview paragraph">The Honda Automotive Laboratories of Ohio (HALO) includes a new aeroacoustic wind tunnel located near Marysville, Ohio that started operations in 2022. This facility provides world-class aerodynamic flow quality and acoustic testing capabilities for the development of both passenger and motorsports vehicles.</div><div class="htmlview paragraph">This closed-return ¾ open jet wind tunnel features a two-position flexible nozzle system with cross sections of 25 m<sup>2</sup> and 18 m<sup>2</sup>, providing wind speeds of up to 250 km/h and 310 km/h, respectively. There is a ±180 degree turntable with boundary layer control systems, and interchangeable single belt and 5-belt moving ground plane (MGP) modules. Extensive applications of acoustic treatment in the test section and throughout the wind tunnel circuit provide a hemi-anechoic test environment and low background noise levels. A temperature control system provides uniform and stable air temperature over an operating environment between 10 °C and 50 °C.</div><div class="htmlview paragraph">The primary instrumentation of the wind tunnel includes the wind speed, temperature, and humidity measurement systems, a 6-component force balance integrated within the turntable, and an acoustic test system (ATS). The ATS includes four planar microphone arrays for external measurements and a spherical microphone array and binaural heads for internal measurements. A flow survey traverse system equipped with a 4-D probe holder mechanism is capable of placing a probe anywhere within the test volume.</div><div class="htmlview paragraph">The HALO facility includes the wind tunnel control room, secure vehicle preparation bays and office spaces for segregated customers, and a vehicle frontal and side area measurement system.</div><div class="htmlview paragraph">This paper provides an introduction to the HALO wind tunnel testing capabilities, design features and development, and the results of the aeroacoustic commissioning program. The background noise level and flow quality characteristics are provided.</div></div>

Implementation and Precision Analysis of Speed Measurement System for Marine Main Engine

The rotational speed of the marine engine plays a critical role in navigation. In practical application, speed measurement was carried out with the help of the centralized control system. In most cases, the speed information would be obtained through a dedicated line, and it would be transmitted to a few special areas, such as the pilot house, the captain’s office, and the controlling center. Consequently, the users could not get the speed information in time, which might increase navigation risk. A speed measurement system independent from the centralized control system of the original engine was proposed and detailed designed in this work. In addition, remote access was realized by network environment configuration. Furthermore, measurement precision was analyzed from theory and experiment. The results indicate that the system works well during long-term operation and the accuracy of measurement meets the requirement. Due to its accuracy and convenience in use, the system can also be widely used in other monitoring situations.

Development and Performance Assessment of Real-time Rotational Speed Measurement System for Agricultural Application

Rotational speed is one of the most important parameters in the performance of any system. It becomes more vital when the rotational speed measurement is required on real-time basis. Measurement of rotational speed has a crucial role in automation of agricultural machineries for various purposes. The existing real-time speed measurement systems are susceptible to the varying working environment. Therefore, it was necessary to study the performance of available sensor. In this study four different sensors (inductive proximity, Infrared (IR), Hall effect and optical proximity sensors) were tested in three different working environments (indoor, outdoor and outdoor dusty condition) for two different spacings (2 and 5 mm) between sensors and target. A laboratory setup was developed to test the performance of the sensors in terms of percentage deviation in rotational speeds measurement compared to actual values. The values were recorded in Secure Digital (SD) card and analysed using full factorial design. The means of the different levels were compared using Tukey’s (b) method. There was significant difference in sensor response for different conditions. The percentage of deviation in speed for Hall effect, inductive proximity, IR and optical proximity sensors varied from 0.55 to 1.03, 1.20 to 32.29, 21.37 to 100.00 and 35.18 to 99.98%, respectively. The study concluded that the Hall effect sensor was more suitable for rotational speed measurement than the other sensors without being affected by working environment.

Pitch and yaw angular speed measurement using Kalman data fusion

Pitch and yaw angular speed measurements are vitally important parameters for monitoring the condition of precision machines. In this letter, we propose a dynamic pitch and yaw angular speed measurement system based on line scan vision. The characteristic line scan image can be considered a discrete time sequence, and each column of pixels represents a different time. A double light-spot centroid and double Gaussian fitting algorithm are developed to obtain the centroid coordinates. Kalman data fusion is employed to enhance the accuracy of the obtained measurement results. The experimental results prove that the proposed method is effective and highly accuracy.

일반 절대위치 인코더를 이용한 회전진동 측정에 관한 연구

A convenient process to measure the rotational vibration of a shaft in a mechanical or electrical rotating system using an ordinary absolute encoder is introduced. The output voltage signal from the encoder is sampled at an appropriate rate with a data recorder. The variation in angular position of the shaft at each time step is calculated based on the output voltage of the encoder. The angular speed of the shaft for a specific time step is then calculated by dividing the angular displacement by the corresponding time interval. The frequency components of the rotational vibration are calculated from the frequency analysis of the series of angular speeds. The validity of this process is examined via computer simulations and simple experiments, showing relatively good correspondence. The proposed method exploits the simple and convenient rotational speed measurement system using an absolute encoder and data recorder. The test results confirm that the proposed method can effectively measure the rotational vibration of a rotating machine with reasonable accuracy.

Toward Simultaneous Localization and Speed Measurement of Mobile Vehicles via RF-ELP

Radio-frequency identification (RFID) electronic license plate (RF-ELP) has been widely used to enable various automatic vehicle identification applications. Endowing RF-ELP with mobile vehicle sensing capabilities, such as localization and speed measurement is of practical importance, yet there is no solution on the shelf. Moreover, the position information is essential for accurate speed measurement, while the related RFID-based vehicular localization and indoor mobile localization methods suffer from at least one of the following major limitations: 1) difficult to deploy in practice; 2) requiring moving speed in advance; 3) only working for indoor-speed vehicles; and 4) not well compatible to frequency-hopping mechanism. To overcome the above limitations, this article proposes an RF-ELP-based mobile vehicle sensing (RESensing) system. RESensing conducts a new signal phase collection strategy to ensure the phase coupling in road-speed cases and converts phases of each interrogation to the relative speed to make it immune to frequency hopping and interinterrogation phase fluctuation. Then, the speed measurement and longitudinal localization are simultaneously performed by solving a nonlinear optimization model. Furthermore, the propagation model and antenna radiation pattern are investigated to facilitate the received signal strength index (RSSI)-based accurate lane-level lateral localization. To our knowledge, RESensing is the first RF-ELP-based speed measurement and localization system for mobile vehicles. The performance of RESensing is evaluated by real experiments under specifications of GB/T 37987 and EPC C1G2, which shows that RESensing achieves the mean speed error ratio of 4.34%, the longitudinal localization error of submeter level, and the lane estimation accuracy of nearly 100%.

An instantaneous speed measurement method based on A/D acquisition method

The measurement of instantaneous speed is often used in the vibration and noise control of equipment. This paper designs an instantaneous speed measurement method based on A/D sampling method. This method mainly obtains the instantaneous speed indirectly by obtaining the square wave signal. The experimental results show that this method is simple and feasible, and provides a reference for the establishment of instantaneous speed measurement system.