Recent studies have established immersive virtual environments (IVEs) as promising tools for studying human thermal states and human–building interactions. One advantage of using immersive virtual environments is that experiments or data collection can be conducted at any time of the year. However, previous studies have confirmed the potential impact of outdoor temperature variations, such as seasonal variations on human thermal sensation. To the best of our knowledge, no study has looked into the potential impact of variations in outdoor temperatures on experiments using IVE. Thus, this study aimed to determine if different outdoor temperature conditions affected the thermal states in experiments using IVEs. Experiments were conducted using a head mounted display (HMD) in a climate chamber, and the data was analyzed under three temperature ranges. A total of seventy-two people participated in the experiments conducted in two contrasting outdoor temperature conditions, i.e., cold and warm outdoor conditions. The in situ experiments conducted in two cases, i.e., cooling in warm outdoor conditions and heating in cold outdoor conditions, were used as a baseline. The baseline in-situ experiments were then compared with the IVE experiments conducted in four cases, i.e., cooling in warm and cold outdoor conditions and heating in warm and cold outdoor conditions. The selection of cooling in cold outdoor conditions and heating in warm outdoor conditions for IVE experiments is particularly for studying the impact of outdoor temperature variations. Results showed that under the experimental and outdoor temperature conditions, outdoor temperature variations in most cases did not impact the results of IVE experiments, i.e., IVE experiments can replicate a temperature environment for participants compared to the ones in the in situ experiments. In addition, the participant’s thermal sensation vote was found to be a reliable indicator between IVE and in situ settings in all studied conditions. A few significantly different cases were related to thermal comfort, thermal acceptability, and overall skin temperature.
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Investigation of the physiological differences in the immersive virtual reality environment and real indoor environment: Focused on skin temperature and thermal sensation
The goal of this research is to investigate and determine whether the effect of an IVE condition on an occupant's environmental sensations and physiological responses is different from the effect of a real environmental condition in the indoor environment. The research included a series of human subject experiments, with 16 participants in an environmental chamber. A thermal quality condition was selected as a primary environmental parameter, based on current IEQ-relevant studies. While the ambient thermal condition was gradually changed from 20 °C to 30 °C, the participants were asked to report their overall thermal sensations. Their skin temperatures were also continuously measured to collect physiological signal information in real time. The results of this experimental study revealed that the participants mostly generated higher skin temperature at the selected seven skin areas. Their reported thermal sensations were significantly higher in the IVE condition, than in the real environment, showing a difference of 12%.
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- Award ID(s):
- 1707068
- NSF-PAR ID:
- 10114040
- Date Published:
- Journal Name:
- Building and environment
- Volume:
- 154
- ISSN:
- 0360-1323
- Page Range / eLocation ID:
- 44-54
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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