Virtual objects have become more tangible with the development of haptic gloves that use electronically controlled electrodes on the fingertips. These electrodes stimulate sensations similar to real touch, which have applications in the gaming sector and the future of touching textiles through the internet. However, Pedro Lopes and his team from the University of Chicago have developed a variant of the haptic glove that doesn’t require electrodes on the fingertips or palms. Despite this, their prototype can generate tactile sensations on the palms.
The team achieved this by placing two electrodes on the outside of each finger and two electrodes on the surface of the hand. With precisely balanced current pulses, they could stimulate tactile sensations on the palm of the hand. The result may seem contradictory, but this is due to the different number of touch cells on the inside and outside of the hand. The skin on the inside of the hand has around 60 times more touch receptors than on the outside, which the researchers used to their advantage.
In experiments, the researchers determined the receptors’ stimulus threshold on the outside and adjusted the current pulses accordingly to generate tactile impressions in 11 zones on the palm of the hand. Eight volunteers tested the innovative haptic glove’s first prototype and reported that they could feel both the shape and size of virtual objects via the artificially excited tactile stimuli while wearing VR glasses.
The team also conducted experiments that superimposed artificial and real tactile stimuli from grasping a coarse rope to kneading a clay mass. The results showed that the real touch impressions were only slightly distorted by the virtual stimuli. The team now plans to optimize the prototype further by focusing on smaller electrodes and generating virtual stimuli that correspond to different textures of a surface.
The potential applications for the haptic glove adaptation are in the field of augmented reality, where fitters, for instance, have to skillfully touch real objects and be guided by virtual stimuli. Lopes and colleagues have presented their invention at the Conference on Human Factors in Computing Systems – CHI 2023 – in Hamburg, where it was well received.
