In the process of exploring new interactions, Wellesley’s HCI lab has a team of students, Cassie Hoef and Jasmine Davis, working with zSpace. The zSpace is a holographic rendering machine capable of displaying objects in 3D using stereoscopic vision. It features: head tracking glasses, a stylus that offers 6 degrees of freedom, and haptic feedback.
In collaboration with Erin Solovey (Drexel), we use fNIRS brain sensing as a supplemental measurement to more traditional performance metrics to investigate the benefits of such techniques for spatial problem solving.
fNIRS is a non-invasive device which sits on the user’s forehead (as shown in the photos above). It shines near-infrared light through the skull and into the brain to measure the amount of oxygenated hemoglobin. The measurement can indicate the amount of workload a user is experiencing which might be a useful indication of how helpful the modes of interacting with the zSpace are.
In order to test this we are using a series of conditions and activities in the interactive stereoscopic 3D environment provided by zSpace to determine if a fNIRS device is a viable option in the collection of supplemental data in an HCI setting. Additional features of zSpace like haptic feedback and stereo vision are toggled between users to assess the fNIRS data’s ability to differentiate between different conditions. During the study the user completes puzzles in our zPuzzle application while wearing the fNIRS device. The levels change in difficulty, so the workload on the brain should change and ideally the change will be detectable between levels.
Some preliminary assessment of the data suggests that there is the possibility of a difference in frustration levels, physical workload, and subjective effort. The brain data shows a higher level of oxy-hemoglobin during the stereo-haptic condition when compared to the stereo-no-haptic condition. We hope further studies will support and strengthen these initial suggestions.
These days, the zSpace team primarily spends their time scheduling and executing user studies in order to collect more data. In the next few weeks, we will be executing 60 more user studies and beginning data analysis.