Human Factor Balance Under the Influence …
299
Fig. 1 Student subjected to
a noise coming from behind
A Kistler force platform was used to determine the area of stability by representing
the positions of the body COP (center of pressure). The platform was connected to
a laptop and we used Bioware for graphical representations and statistical results.
The subjects were instructed to stand relaxed for 30 s on the force platform in order
to determine a reference stability area. Then, without warning, they were subjected
to sudden noises coming from different directions, as shown in Fig. 1. Frequencies,
types of sounds, and intensities were also changed in order to determine which will
produce stronger reactions by loss of balance.
Results were recorded and analyzed using the dedicated software, as mentioned
before (Bioware).
3 Results and Discussions
In order to have a reference for the stability area, all subjects were first required
to stand on the force platform and assume a relaxed position for 30 s. The stability
areas were in most situations compact and sways on axis Ox (lateral) and Oy (anteroposterior) were below 0.025 m, like in the example shown in Fig. 2.
The test subjects were divided into four groups; some of them being exposed
to sounds coming from front, some of them from behind and some from left side
or right side. Also the types of the waves were changed, without telling them, into
299
Fig. 1 Student subjected to
a noise coming from behind
A Kistler force platform was used to determine the area of stability by representing
the positions of the body COP (center of pressure). The platform was connected to
a laptop and we used Bioware for graphical representations and statistical results.
The subjects were instructed to stand relaxed for 30 s on the force platform in order
to determine a reference stability area. Then, without warning, they were subjected
to sudden noises coming from different directions, as shown in Fig. 1. Frequencies,
types of sounds, and intensities were also changed in order to determine which will
produce stronger reactions by loss of balance.
Results were recorded and analyzed using the dedicated software, as mentioned
before (Bioware).
3 Results and Discussions
In order to have a reference for the stability area, all subjects were first required
to stand on the force platform and assume a relaxed position for 30 s. The stability
areas were in most situations compact and sways on axis Ox (lateral) and Oy (anteroposterior) were below 0.025 m, like in the example shown in Fig. 2.
The test subjects were divided into four groups; some of them being exposed
to sounds coming from front, some of them from behind and some from left side
or right side. Also the types of the waves were changed, without telling them, into