HandMorph ー
In this paper, we engineered HandMorph, an exoskeleton that approximates the experience of having a smaller hand. Leveraging the plasticity of our body's representation, we proposed and verified an illusion that transforms one's grasping range into that of a someone with a smaller hand. HandMorph achieves this using mechanical links that transmit motion from the wearer's fingers to a smaller soft hand with five fingers. As such, HandMorph miniaturizes a wearer's grasping range while transmitting haptic feedback.
Unlike other size- or grasp-illusions based on virtual reality, HandMorph achieves this in the user's real environment while preserving the user's physical and social contexts. As such, our device can be integrated into the user's workflow, e.g., to allow product designers to momentarily change their grasp into that of a child while evaluating a toy prototype.
We conducted two user studies to validate HandMorph. In our first user study, we found out that the participants' perceived objects as being larger when wearing HandMorph, which suggests that their size perception was transformed as if having a smaller hand.
In our second user study, we assessed the experience of using HandMorph as an assistive tool for designing a simple toy trumpet for children. We found that participants felt more confident in their toy design when using HandMorph to validate its ergonomics. We believe that, unlike consulting human factors ergonomic charts, the somatosensory feedback felt while using HandMorph helped participants to understand the usability of their designs in a more embodied manner.
Lastly, we find that our device is unique in that it enables the wearer, especially designers, to gain embodied knowledge of the challenges of those with a smaller grasp: children, individuals of short stature or with dwarfism, and so forth.
Jun Nishida, Soichiro Matsuda, Hiroshi Matsui, Shan-Yuan Teng, Ziwei Liu, Kenji Suzuki, and Pedro Lopes. 2020. HandMorph: a Passive Exoskeleton that Miniaturizes Grasp. In Proceedings of the 33rd Annual ACM Symposium on User Interface Software and Technology (UIST '20). Association for Computing Machinery, New York, NY, USA, 565–578. https://doi.org/10.1145/3379337.3415875