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).