scholarly journals The Validity and Reliability of 1-Hz and 5-Hz Global Positioning Systems for Linear, Multidirectional, and Soccer-Specific Activities

2010 ◽  
Vol 5 (4) ◽  
pp. 448-458 ◽  
Author(s):  
Matthew D. Portas ◽  
Jamie A. Harley ◽  
Christopher A. Barnes ◽  
Christopher J. Rush

Purpose:The study aimed to analyze the validity and reliability of commercially available nondifferential Global Positioning System (NdGPS) devices for measures of total distance during linear, multidirectional and soccer-specific motion at 1-Hz and 5-Hz sampling frequencies.Methods:Linear (32 trials), multidirectional (192 trials) and soccer-specific courses (40 trials) were created to test the validity (mean ± 90% confidence intervals), reliability (mean ± 90% confidence intervals) and bias (mean ± 90% confidence intervals) of the NdGPS devices against measured distance. Standard error of the estimate established validity, reliability was determined using typical error and percentage bias was established.Results:The 1-Hz and 5-Hz data ranged from 1.3% ± 0.76 to 3.1% ± 1.37 for validity and 2.03% ± 1.31 to 5.31% ± 1.2 for reliability for measures of linear and soccer-specific motion. For multidirectional activity, data ranged from 1.8% ± 0.8 to 6.88% ± 2.99 for validity and from 3.08% ± 1.34 to 7.71% ± 1.65 for reliability. The 1-Hz underestimated some complex courses by up to 11%.Conclusions:1-Hz and 5-Hz NdGPS could be used to quantify distance in soccer and similar field-based team sports. Both 1-Hz and 5-Hz have a threshold beyond which reliability is compromised. 1-Hz also underestimates distance and is less valid in more complex courses.

2009 ◽  
Vol 4 (3) ◽  
pp. 381-393 ◽  
Author(s):  
Carl Petersen ◽  
David Pyne ◽  
Marc Portus ◽  
Brian Dawson

Purpose:The validity and reliability of three commercial global positioning system (GPS) units (MinimaxX, Catapult, Australia; SPI-10, SPI-Pro, GPSports, Australia) were quantified.Methods:Twenty trials of cricket-specific locomotion patterns and distances (walking 8800 m, jogging 2400 m, running 1200 m, striding 600 m, sprinting 20- to 40-m intervals, and run-a-three) were compared against criterion measures (400-m athletic track, electronic timing). Validity was quantified with the standard error of the estimate (SEE) and reliability estimated using typical error expressed as a coefficient of variation.Results:The validity (mean ± 90% confidence limits) for locomotion patterns walking to striding ranged from 0.4 ± 0.1 to 3.8 ± 1.4%, whereas for sprinting distances over 20 to 40 m including run-a-three (approx. 50 m) the SEE ranged from 2.6 ± 1.0 to 23.8 ± 8.8%. The reliability (expressed as mean [90% confidence limits]) of estimating distance traveled by walking to striding ranged from 0.3 (0.2 to 0.4) to 2.9% (2.3 to 4.0). Similarly, mean reliability of estimating different sprinting distances over 20 to 40 m ranged from 2.0 (1.6 to 2.8) to 30.0% (23.2 to 43.3).Conclusions:The accuracy and bias was dependent on the GPS brand employed. Commercially available GPS units have acceptable validity and reliability for estimating longer distances (600–8800 m) in walking to striding, but require further development for shorter cricket-specifc sprinting distances.


Author(s):  
Anna M.J. Iveson ◽  
Malcolm H. Granat ◽  
Brian M. Ellis ◽  
Philippa M. Dall

Objective: Global positioning system (GPS) data can add context to physical activity data and have previously been integrated with epoch-based physical activity data. The current study aimed to develop a framework for integrating GPS data and event-based physical activity data (suitable for assessing patterns of behavior). Methods: A convenience data set of concurrent GPS (AMOD) and physical activity (activPAL) data were collected from 69 adults. The GPS data were (semi)regularly sampled every 5 s. The physical activity data output was presented as walking events, which are continuous periods of walking with a time-stamped start time and duration (to nearest 0.1 s). The GPS outcome measures and the potential correspondence of their timing with walking events were identified and a framework was developed describing data integration for each combination of GPS outcome and walking event correspondence. Results: The GPS outcome measures were categorized as those deriving from a single GPS point (e.g., location) or from the difference between successive GPS points (e.g., distance), and could be categorical, scale, or rate outcomes. Walking events were categorized as having zero (13% of walking events, 3% of walking duration), or one or more (52% of walking events, 75% of walking duration) GPS points occurring during the event. Additionally, some walking events did not have GPS points suitably close to allow calculation of outcome measures (31% of walking events, 22% of walking duration). The framework required different integration approaches for each GPS outcome type, and walking events containing zero or more than one GPS points.


Author(s):  
Markel Rico-González ◽  
José Pino-Ortega ◽  
Fabio Y Nakamura ◽  
Felipe Arruda Moura ◽  
Daniel Rojas-Valverde ◽  
...  

The main aim of this work was to review the use of technological tracking methods to assess collective spatial-positioning variables in team sports. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and PICO design for systematic reviews, study identification was performed in four databases (PubMed, SPORTDiscus, ProQuest Central, and Web of Science). Articles were selected if they focused on player position and technological tracking methods. After duplicate removal, 2194 articles were identified based on the established search criteria, of which 72 articles were selected and analysed. Semi-automatic optic-based systems, Global Positioning System/Global Navigation Satellite Systems, and local positioning systems were used in 60%, 33% and 7% of the studies, respectively. All studies that measured tactical variables by local positioning system technology in team sports used local position measurement technology. Optic-based systems were used more often in the early years to analyse collective tactical behaviour during competition. Later, Global Positioning System/Global Navigation Satellite Systems became more frequent to measure behaviour in team sports during the training process. The possibility of using the same system during competition and training will facilitate the assessment of collective tactical behaviour in team sports.


Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 2118
Author(s):  
Óscar de Francisco Ortiz ◽  
Irene Ortiz ◽  
Antonio Bueno

In any precision manufacturing process, positioning systems play a very important role in achieving a quality product. As a new approach to current systems, camera-LCD positioning systems are a new technology that can provide substantial improvements enabling better accuracy and repeatability. However, in order to provide stability to the system a global positioning system is required. This paper presents an improvement of a positioning system based on the treatment of images on an LCD in which a new algorithm with absolute reference has been implemented. The method is based on basic geometry and linear algebra applied to computer vision. The algorithm determines the spiral center using an image taken at any point. Consequently, the system constantly knows its position and does not lose its reference. Several modifications of the algorithm are proposed and compared. The simulation and test of the algorithm provide an important improvement in the reliability and stability of the positioning system providing errors of microns for the calculation of the global position used by the algorithm.


1998 ◽  
Vol 51 (3) ◽  
pp. 382-393 ◽  
Author(s):  
M. Tsakiri ◽  
M. Stewart ◽  
T. Forward ◽  
D. Sandison ◽  
J. Walker

The increasing volume of traffic in urban areas has resulted in steady growth of the mean driving time on fixed routes. Longer driving times lead to significantly higher transportation costs, particularly for vehicle fleets, where efficiency in the distribution of their transport tasks is important in staying competitive in the market. For bus fleets, the optimal control and command of the vehicles is, as well as the economic requirements, a basic function of their general mission. The Global Positioning System (GPS) allows reliable and accurate positioning of public transport vehicles except within the physical limitations imposed by built-up city ‘urban canyons’. With a view to the next generation of satellite positioning systems for public transport fleet management, this paper highlights the limitations imposed on current GPS systems operating in the urban canyon. The capabilities of a future positioning system operating in this type of environment are discussed. It is suggested that such a system could comprise receivers capable of integrating the Global Positioning System (GPS) and the Russian equivalent, the Global Navigation Satellite System (GLONASS), and relatively cheap dead-reckoning sensors.


2020 ◽  
Author(s):  
José Pino-Ortega ◽  
Markel Rico-González

The use of valid, accurate and reliable systems is fundamental to warrant a high-quality data collection and interpretation. In 2015, FIFA created a department of Electronic Performance and Tracking systems, collecting under this name the more used tracking systems in team sport setting: high-definition cameras, Global Positioning Systems, and Local Positioning Systems. To date, LPS systems proved to be valid and accurate in determining the position and estimating distances and speeds. However, it is hypothesized that between LPS, ultra-wide band (UWB) is the most promising technology for the future. Thus, this chapter was aimed to make an update about UWB technology in sport: the FIFA’s regulation, manufacturer that provide this technology, the research articles that assessed validity and reliability of UWB technology, and the criteria standard for the use of this technology.


Author(s):  

The article deals with the history of the development of automotive on-Board control systems since the late 60s of the last century to the present time, the assessment of their effectiveness. The perspective directions of development of onboard systems of control of a technical condition with use of global positioning systems GLONASS and GPS, the technology of "augmented reality" are described. Keywords diagnostics, OBD, KAN Protocol, global positioning system GLONASS and GPS, "augmented reality" technology


2012 ◽  
Vol 263-266 ◽  
pp. 346-349 ◽  
Author(s):  
Hong Shi ◽  
Dong Hai Qiao

Geophysical measurement relies on the positioning accuracy of GPS (global positioning system). Usually the positioning accuracy is area dependent. This paper uses a commercially available GPS receiver to verify its positioning accuracy with practical measurement in a small area. With a measurement setup in an open ground, the results show that even for the fixed point, the GPS measured positioning error of about 0.234 meter could be observed for a period of time. Of 12 GPS measured distance errors, only one is about 5.7 meters, all others are within the range of 3-5 meters of GPS receiver specification.


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