Concurrent validity, inter-unit reliability and biological variability of a low-cost pocket radar for ball velocity measurement in soccer and tennis

2020 ◽  
pp. 1-8
Author(s):  
Alejandro Hernández-Belmonte ◽  
Alejandro Sánchez-Pay
Keyword(s):  
Velocity Measurement ◽  
Concurrent Validity ◽  
Low Cost ◽  
Biological Variability ◽  
Ball Velocity

scholarly journals MEMS Based SINS/OD Filter for Land Vehicles’ Applications

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Huisheng Liu ◽  
Zengcai Wang ◽  
Susu Fang ◽  
Chao Li
Keyword(s):  
Navigation System ◽  
Velocity Measurement ◽  
Microelectromechanical Systems ◽  
Low Cost ◽  
Detection Algorithm ◽  
Measurement Unit ◽  
Integrated Navigation ◽  
Integrated Navigation System ◽  
Land Vehicles ◽  
Mems Imu

A constrained low-cost SINS/OD filter aided with magnetometer is proposed in this paper. The filter is designed to provide a land vehicle navigation solution by fusing the measurements of the microelectromechanical systems based inertial measurement unit (MEMS IMU), the magnetometer (MAG), and the velocity measurement from odometer (OD). First, accelerometer and magnetometer integrated algorithm is studied to stabilize the attitude angle. Next, a SINS/OD/MAG integrated navigation system is designed and simulated, using an adaptive Kalman filter (AKF). It is shown that the accuracy of the integrated navigation system will be implemented to some extent. The field-test shows that the azimuth misalignment angle will diminish to less than 1°. Finally, an outliers detection algorithm is studied to estimate the velocity measurement bias of the odometer. The experimental results show the enhancement in restraining observation outliers that improves the precision of the integrated navigation system.

A Low Cost Velocity Measurement System Design for Rotary Machinery

2010 ◽  
Author(s):  
Cagatay Cakir ◽  
Hasan Koruk ◽  
Burak Ulas
Keyword(s):  
System Design ◽  
Measurement System ◽  
Velocity Measurement ◽  
Practical Problem ◽  
Low Cost ◽  
Measurement Systems ◽  
Rotary Machinery ◽  
Measurement Devices ◽  
Motorized Vehicles ◽  
Sufficient Precision

Today, as the importance of system automation increases, measurement systems become more and more important. Consequently, in many applications, from washing machines, motorized vehicles, robots to nuclear turbine reactors, velocity measurement is inevitable. In industry, velocity is widespreadly needed to be measured. Besides that researchers through the globe need such measurement devices in their studies. On the other hand, to be able to make a correct measurement, it may be needed to pay much on measuring equipments while the economical issue is sometimes the reason for the research does not continue on or even not begin. So, it has always been a practical problem for both industry and researchers not to be able to measure the rotating velocity of machinery with both sufficient precision and low cost. In this paper, a very low cost but still precise velocity measurement system design is introduced, explained and discussed. First, building up of the sensor circuit and basic components of the system are introduced. Then, data acquisition and signal processing of the system are explained. Finally, advantages of the system are discussed and some conclusions are given.

scholarly journals Validity and Reliability of Isometric-Bench for Knee Isometric Assessment

2020 ◽  
Vol 17 (12) ◽  
pp. 4326
Author(s):  
Johnny Padulo ◽  
Nebojša Trajković ◽  
Drazen Cular ◽  
Zoran Grgantov ◽  
Dejan M. Madić ◽  
...  
Keyword(s):  
Knee Flexion ◽  
Concurrent Validity ◽  
High Reliability ◽  
Low Cost ◽  
Isometric Strength ◽  
Systematic Bias ◽  
Validity And Reliability ◽  
Isokinetic Dynamometer ◽  
Isometric Forces ◽  
Flexion And Extension

There is a strong need for a new, probably cheaper, smaller, and more portable isometric dynamometer. With this aim, we investigated the concurrent validity and reliability of a low-cost portable dynamometer to measure the isometric strength of the lower limb. Seventeen young participants (age 16.47 ± 0.51 years) were randomly assessed on three different days for knee flexion and extension isometric forces with two different devices: a commonly used isokinetic dynamometer (ISOC) and a portable isometric dynamometer prototype (ISOM). No significant differences were observed between the ISOC and the ISOM (all comparisons p > 0.05). Test–retest comparison showed the ISOM to have high reliability (ICC 0.879–0.990). This study showed that measurements with the ISOM could be performed without systematic bias and with high reliability. The ISOM is a device that is able to assess knee isometric strength with excellent concurrent validity and reliability.

Study on Velocity Measurement of Gas/Solid Flow Based on Electrostatic Sensor

2014 ◽  
Vol 614 ◽  
pp. 275-278
Author(s):  
Yu Tang ◽  
Xiang Deng ◽  
Shuo Tian
Keyword(s):  
Measurement System ◽  
Velocity Measurement ◽  
Flow Measurement ◽  
Cross Correlation ◽  
Low Cost ◽  
High Sensitivity ◽  
Two Phase ◽  
Solid Flow ◽  
Correlation Algorithm ◽  
Electrostatic Induction

Electrostatic sensor is based on the principle of electrostatic induction. It is widely used for gas/solid two-phase flow measurement because it has the advantages of simple structure, high sensitivity, low cost, etc. In this paper, a velocity measurement system of gas/solid flow based on electrostatic sensor and cross-correlation algorithm is discussed. Electrostatic sensor with circular electrode is adopted. By COMSOL optimum simulation, the axial length of the electrode is designed. The signal conditioning circuits are discussed and cross-correlation algorithm is analyzed. The initial experimental results demonstrate that the velocity measurement system of gas/solid flow designed in this paper is feasible.

scholarly journals Low cost NodeMcu based development water rocket measurement system applied to STEM education

2019 ◽  
Author(s):  
Andi Susilo ◽  
Yasmiati ◽  
Ahmad Apandi
Keyword(s):  
Stem Education ◽  
Measurement System ◽  
Velocity Measurement ◽  
High Speed ◽  
Low Cost ◽  
Smartphone Application ◽  
Water Volume ◽  
Learning Tools ◽  
Rocket Measurement ◽  
School Activity

Water rockets have become one of learning tools for STEM Education in schools. Generally water rockets make in school activity have no parachute load, altitude, and velocity measurement. Rocket can go any direction and also will cause hard collision to the ground that break the high speed rocket. It will take time and need more cost to make a new one for students. This study propose the low cost NodeMcu based water rocket measurement system to solve the problem. Altitude and velocity measurement are added and deployment system to release the parachute to make water rocket fall to the ground smoothly. Smartphone application used to monitor altitude and velocity of water rocket. Variables consist of water volume and air pressure. Five experiments had been conducted and recorded. The result found that the system could calculate Altitude, Velocity, and Deployment System also could release the parachute automatically in Coasting Descent position.

An effective, low-cost method to improve the movement velocity measurement of a smartphone app during the bench press exercise

2021 ◽  
pp. 175433712110580
Author(s):  
Wladymir Külkamp ◽  
Jairo L Rosa-Junior ◽  
Jonathan Ache-Dias ◽  
Lorival J Carminatti
Keyword(s):  
Older Adults ◽  
Velocity Measurement ◽  
Bench Press ◽  
Low Cost ◽  
Reference Method ◽  
Velocity Measurements ◽  
Range Of Movement ◽  
Mean Velocity ◽  
Movement Velocity ◽  
The Mean

Some studies have reported considerable errors in the movement velocity measurement when using the My Lift app. This study aimed to investigate whether these errors may be related to the use of a range of movement (ROM) statically measured prior to the movement (ROMMYLIFT) instead of ROM dynamically monitored. Ten young adults performed two repetitions of the bench press exercise on a Smith machine with loads that allowed two velocity conditions (above and below 0.6 m s−1). The exercises were monitored by the My Lift app, a magnet and a rotary encoder. After, 15 older adults performed the same exercise at different percentages of 1RM, monitored by the My Lift app and a magnet. The results revealed that ROM dynamically obtained by encoder (reference method) with the mean velocity above (0.497 ± 0.069 m) and below (0.450 ± 0.056 m) 0.6 m s−1 were quite different ( p < 0.05; large effect) from the ROMMYLIFT (0.385 ± 0.040 m). These errors provided highly biased and heteroscedastic mean velocity measurements (mean errors approximately 22%). The errors observed in adults were also observed in the older participants, except for loads equal to 85% of 1RM. The magnet method proved to be valid, presenting measurements very close to the encoder (mean errors approximately 1.7%; r > 0.99). In conclusion, the use of ROMMYLIFT is inadequate, as the higher the movement velocity, the higher the errors, both for young and older adults. Thus, to improve the measurement of the My Lift app, it is recommended that the magnet method be used in conjunction with the app to more accurately determine the ROM.

scholarly journals Proof-of-concept and concurrent validity of a prototype headset to assess peak oxygen uptake without a face mask

2022 ◽  
Vol 15 (1) ◽  
Author(s):  
Peter Düking ◽  
Philipp Kunz ◽  
Florian A. Engel ◽  
Helena Mastek ◽  
Billy Sperlich
Keyword(s):  
Oxygen Uptake ◽  
Concurrent Validity ◽  
Low Cost ◽  
New Technology ◽  
Face Mask ◽  
Peak Oxygen Uptake ◽  
Cycle Ergometer ◽  
Proof Of Concept ◽  
Criterion Measure ◽  
Test Retest Reliability

Abstract Objective Portable gas exchange instruments allow the assessment of peak oxygen uptake (V̇O2peak) but are often bulky, expensive and require wearing a face mask thereby limiting their routine application. A newly developed miniaturized headset (VitaScale, Nuremberg, Germany) may overcome these barriers and allow measuring V̇O2peak without applying a face mask. Here we aimed (i) to disclose the technical setup of a headset incorporating a gas and volume sensor to measure volume flow and expired oxygen concentration and (ii) to assess the concurrent criterion-validity of the headset to measure V̇O2peak in 44 individuals exercising on a stationary cycle ergometer in consideration of the test–retest reliability of the criterion measure. Results The coefficient of variation (CV%) while measuring V̇O2peak during incremental cycling with the headset was 6.8%. The CV% for reliability of the criterion measure was 4.0% for V̇O2peak. Based on the present data, the headset might offer a new technology for V̇O2peak measurement due to its low-cost and mask-free design.

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