, , ,
Volume 10, Issue 4 (10-2012)
Abstract
Technology can provide safety in physical practices and improving the
performance of these activities, so manufacturing of equipments for these
purposes has been considered widely. The aim of the present paper was design
and fabrication of three-axis accelerometer. hree acceleration sensors, three
gyroscopes for angular velocity measurement, a microcontroller for converting
analog data to digital, a semiconductor memory for storing the sampled data, a
rechargeable battery and a spreadsheet in MATLAB environment have been
used. In order to examine the validity of fabricated instrument, the earth gravity
acceleration in three perpendicular axes have been measured and compared
with 9.8m/S2. In order to examine the reliability of the fabricated accelerometer
the ICC and test-re-test method have been used. The results showed that the
accelerometer has both reliability and validity. Due to its special features, it
enables us to sample in the offline mode and wireless manner. Such system
may be used for
N Boroushak, H Khoshnoodi, H Daneshmandy, M Eslami,
Volume 17, Issue 17 (4-2019)
Abstract
Nowadays there is no specific and effective standard for evaluating the helmets in martial arts which it has caused a lot of brain damages. The purpose of this study was designing and modeling a helmet assessment machine in martial arts, based on dynamic’s parameters and criteria. SolidWorks, Adams and Catia softwares were used for designing this machine. Also, In order to build this machine, an artificial head that equipped with force and acceleration sensors and a mechanical arm for applying impact to the head were used. The validation of the machine was done by comparing its results (impact force, linear acceleration and rotational acceleration) with the results obtained from the simulated model in the computer. The Pearson correlation coefficient of 0.9 that obtained from this comparison indicates that the results of this machine are correct. To confirm the reliability of the machine, an Intraclass Correlations was used, the results showed values of 0.7 and greater than that and it also confirmed the appropriate repeatability of the machine. According to the results of this study, due to the considering the important parameters of linear and rotational acceleration and the impact force in evaluating helmets and investigating the mechanism of head injury in the conditions close to competition ones, the device can be an appropriate equipment for more accurate measurement of helmets in martial arts.
