Examining the Effects of Altered Avatars on Perception-Action in Virtual Reality

In virtual reality avatars are animated graphical representation of a person embedded in a virtual environment. Previous research has illustrated the benefits of having an avatar when perceiving aspects of virtual reality. We studied the effect that a non-faithful, or altered, avatar had on the perception of one\u27s action capabilities in VR. In Experiment 1, one group of participants acted with a normal, or faithful, avatar and the other group of participants used an avatar with an extended arm, all in virtual reality. In Experiment 2, the same methodology and procedure was used as in Experiment 1, except only the calibration phase occurred in VR, while the remaining reaches were completed in the real world. All participants performed reaches to various distances. The results of these studies show that calibration to altered dimensions of avatars is possible after receiving feedback while acting with the altered avatar. Further, calibration occurred more quickly when feedback was initially used to transition from a normal avatar to an altered avatar than when later transitioning from the altered avatar arm back to the normal avatar arm without feedback. The implications of these findings for training in virtual reality simulations and transfer back to the real world are also discussed

Perception-Action System Calibration in the Presence of Stable and Unstable Perceptual Perturbations

Actors are able to calibrate to various changes to both their own abilities and their surrounding environments. Most calibration studies have examined recalibration to stable perturbations (i.e., a single, constant change). However, numerous real-world experiences involve perturbations that do not remain constant. The present studies investigated the effect of varying perturbations on postural sway and prospective control. It was hypothesized that short-timescale variations of a perturbation would affect participants\u27 ability to recalibrate. Specifically, the different patterns of perturbation would result in a change to postural sway that would mediate the relationship between the condition and the ability to calibrate. It was found that accuracy was dependent on the type of environmental conditions of the perturbation change (i.e., the rate of change or the pattern of change). However, in general, calibration effects were found for all conditions. The different perturbations also affected the amount of postural sway. The proposed mediated relationship was not supported by this series of experiments. However, this is most likely due to the task not creating enough variability within the variables of interest. The results of these experiments provide further evidence for perception-action system calibration mechanism through task-relevant feedback

Toward New Ecologies of Cyberphysical Representational Forms, Scales, and Modalities

Research on tangible user interfaces commonly focuses on tangible interfaces acting alone or in comparison with screen-based multi-touch or graphical interfaces. In contrast, hybrid approaches can be seen as the norm for established mainstream interaction paradigms. This dissertation describes interfaces that support complementary information mediations, representational forms, and scales toward an ecology of systems embodying hybrid interaction modalities. I investigate systems combining tangible and multi-touch, as well as systems combining tangible and virtual reality interaction. For each of them, I describe work focusing on design and fabrication aspects, as well as work focusing on reproducibility, engagement, legibility, and perception aspects