Vpliv navidezne višine na posturalni nadzor človeka

KEZIĆ, SANJA (author), Mihelj, Matjaž (mentor), Babič, Jan (comentor)

Namen tega dela je bil simulacija dvigala s kombinacijo navidezne resničnosti in robotske platforme. S platformo smo ustvarili realne pospeške, z navideznim okoljem pa smo dosegli človeško percepcijo višine. Kljub majhnim premikom platforme, ki so približno 20 cm, naj bi posameznik dobil realen občutek dviga iz 0,8 m na 3,2 m. Pri tem smo poskušali preučiti spremembe človeškega posturalnega nadzora in zaznavanje strahu, tesnobe oziroma nelagodnosti. Opazovali smo središče mase ter središče porazdelitve sile na podlago, psihološki (vprašalniki) in fiziološki odziv (prevodnost in temperatura kože) na višini 0,8 m in 3,2 m. Pri študiji je sodelovalo 20 mladih prostovoljcev brez strahu pred višino. S pomočjo pritiskovnih plošč in sistemom za zajem gibanja smo opazovali težišče telesa (COP in COM). Analizirali smo povprečno vrednost, povprečno frekvenco močnostnega spektra (MPF) ter efektivno vrednost (RMS). Pokazali smo, da se tudi pri posameznikih, ki se ne bojijo višine, s posturalno grožnjo pojavijo spremembe v čustvenem in fiziološkem stanju, pri tem pa se poostri posturalni nadzor. Z izpostavljenostjo višini se poveča tesnobnost, strah, prevodnost kože ter povprečna frekvenca močnostnega spektra COP in COM podatkov, pri tem pa se zmanjša stabilnost, zaupanje, temperatura na površini kože ter efektivna vrednost oziroma amplituda COP in COM. Odziv na višino se kaže tudi s spremembo povprečnih vrednostih COP in COM v smeri naprej/nazaj, saj se posameznik po dvigu nagne stran od roba. Rezultati te študije so potencialno uporabni pri načrtovanju virtualnih okolij, ki bodo v pomoč pri varnem ovrednotenju človekovega odziva na nenadno spremembo višine, ugotavljanju dejavnikov tveganja padca in oceni novih strategij za preprečevanje padca. Uporabno je pri rehabilitaciji starejših, ki imajo probleme s pomanjkanjem ravnotežja ter zdravljenju psiholoških bolezni, kot je strah pred višino (akrofobija).

• Language: Slovenian
• Keywords: posturalni nadzor, posturalna anksioznost, posturalna grožnja, akrofobija, navidezna resničnost (VR), center mase (COM), center pritiska (COP), elektrodermalna aktivnost (EDA), Stewartova ploščad
• Work type: Master's thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2019
• PID: 20.500.12556/RUL-113022
• Publication date in RUL: 29.11.2019

KEZIĆ, SANJA, 2019, Vpliv navidezne višine na posturalni nadzor človeka [online]. Master’s thesis. [Accessed 15 June 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=113022

Secondary language

• Language: English
• Title: Impact of virtual elevation on human postural control

Abstract

The purpose of this work was to simulate movement of an elevator lift with a combination of virtual reality and a robotic platform. With the platform we created real accelerations and with the virtual environment we achieved human perception of height. Despite the limited range of motion of the parallel robotic platform, which is approximately 20 cm in the vertical direction, the subject is expected to get a sense of lifting from 0.8 m to 3.2 m. The platform raised with an initial acceleration of 1,35 m/s2 for 17 cm, at the same time we raised the platform in the virtual world for 2,4 m. We examined changes in human postural control and perceptions of fear, anxiety, or discomfort. We observed psychological (questionnaires) and physiological responses (conductivity and skin temperature) at a height of 0.8 m and 3.2 m. The experiment involved 20 young volunteers without fear of heights. With force plates and the motion capture system, we observed the center of pressure and center of gravity of the body (COP and COM). We analyzed the mean value, the mean power frequency and the root mean square of COM and COP data. With this experiment we demonstrated that even individuals without fear of heights, feel changes in their emotional and physiological state, while also amplifying their postural control. Height exposure increases anxiety, fear, skin conductivity and mean power frequency of COP and COM displacement, while reducing stability, confidence, skin surface temperature and the root mean square of COP and COM. The response to the postural threat is also reflected in the average COP and COM values in the anterior posterior direction as the individual leans away from the edge after lifting. The results of this study are potentially useful in designing virtual environments that will assist in the safe evaluation of the human response to uplift, identifying risk factors for a fall and evaluating new fall prevention strategies. It is useful for the rehabilitation of the elderly, who have problems with their lack of balance and the treatment of psychological diseases such as fear of heights (acrophobia).

• Keywords: postural control, postural threat, anxiety, acrophobia, virtual reality, robotic platform, Stewart platform, electrodermal activity (EDA), center of pressure (COP), center of mass (COM), base of support (BOS)