In my MA-thesis project "Haptic in Virtual Reality" focusing on research-oriented design I approached the question whether and/or to what extent digital visuals can influence tactile
perception. First ideas for this project came to mind when I tested the Oculus DK2 with some frieds of mine because most of them tried to reach out into the digital space (despite no handtracking).
I already owned a Leap Motion Controller but had not tested it at that point, so we went and tried out all available software from the Leap VR category in its app store. The demo "Weightless"
was something else in particular. You could toss around space debris in weightless space inside a virtual space station. Strangely one of the objects, a chain, almost felt like it could be touched.
That in turn brought me to my research question because I kept asking myself: could this experience be turned around or could a digital object actually be combined with a real tactile sensation?
What kind of effects might a setup like that produce and could you even deceive the tactile sense by presenting a dissonant visual stimulus at the same time?
So my main focus became doing a small qualitative study on this topic and therefore developing a software that could facilitate such a test environment. It soon became clear, that touching an object
while still having accurate handtracking was not that easy: since the Leap works with a monochrome contrast in the infrared spectrum to isolate the hand, a suitable underlay had to be found.
After having decided to pick a simple doormat as underlay and laquered a wooden bowl with matte black paint the tracking seemed to work while touching the object. Afterwards three
different digital materials were created for use during the test that would be visually presented in VR, while in the real world touching the same material three times while describing the experience.
Although the given group of testsubjects was not statistically significant there were strong indicators for people almost always being able to recognize the real material by touching it.
The dissonance with the visual input was mentioned by the testsubjects as irritating but did not seem to affect the tactile sensation. There were other insights to be found though:
When presented with these incongruent stimuli a lot of participants tried to use other inputs to distiguish the real material from the visual representation, like knocking on the bowl, scratching,
lifting and smelling or even looking away to isolate the tactile sensation. After these experiments there is still a lot to learn and further research will be done in the future.