TY - JOUR
N2 - The accuracy of vehicle speed measured by a speedometer is analysed. The stress on the application of skew normal distribution is laid. The accuracy of measured vehicle speed depends on many error sources: construction of speedometer, measurement method, model inadequacy to real physical process, transferring information signal, external conditions, production process technology etc. The errors of speedometer are analysed in a complex relation to errors of the speed control gauges, whose functionality is based on the Doppler effect. Parameters of the normal distribution and skew normal distribution were applied in the errors analysis. It is shown that the application of maximum permissible errors to control the measuring results of vehicle speed gives paradoxical results when, in the case of skew normal distribution, the standard deviations of higher vehicle speeds are smaller than the standard deviations of lower speeds. In the case of normal distribution a higher speed has a greater standard deviation. For the speed measurements by Doppler speed gauges it is suggested to calculate the vehicle weighted average speed instead of the arithmetic average speed, what will correspond to most real dynamic changes of the vehicle speed parameters.
L1 - http://journals.pan.pl/Content/113102/PDF/09_MMS_3_INTERNET.pdf
L2 - http://journals.pan.pl/Content/113102
PY - 2019
IS - No 3
EP - 559
DO - 10.24425/mms.2019.129583
KW - vehicle speed
KW - speedometer
KW - maximum permissible error
KW - skew normal distribution
KW - errors
A1 - Skeivalas, Jonas
A1 - Paršeliūnas, Eimuntas
A1 - Putrimas, Raimundas
A1 - Šlikas, Dominykas
PB - Polish Academy of Sciences Committee on Metrology and Scientific Instrumentation
VL - vol. 26
DA - 2019.09.23
T1 - On statistical estimations of vehicle speed measurements
SP - 551
UR - http://journals.pan.pl/dlibra/publication/edition/113102
T2 - Metrology and Measurement Systems
ER -