Somatosensory Interaction: Investigating Mechanoreception, Thermoception, and Proprioception for On-Body Haptic Feedback

Haptics are an important factor to make virtual worlds and remote interpersonal interaction tangible. While current technological advances, such as Virtual Reality (VR), are reaching the mass market, they are primarily visual while available haptic devices are mostly limited to vibrotactile stimuli, such as smartphone notifications or embedded in game controllers. However, haptic feedback consists of more components that make an experience physically perceivable and lifelike. In addition to the vibrotactile stimulation of fine mechanoreception, these also incorporate stronger forces addressing pressure-based mechanoreception, temperature perceived by thermoception, and body position and movement perceived by proprioception, which are all parts of the somatosensory system. Consequently, to get closer to a full haptic experience, haptics need to be considered in the broader context of the complete somatosensory system. In this thesis, novel haptic concepts will be introduced and implemented in prototypical systems to investigate them in a series of user studies, leading to a better understanding of somatosensory interaction. In this context, this dissertation provides six major contributions: (1) The first contribution presents a systematic investigation of fine and subtle mechanoreception involving vibrotactile stimuli on the hand for guidance and target acquisition. (2) The second contribution investigates more intense and pressure-based mechanoreception that employs pneumatically actuated air cushions to create immediate pressure sensations. (3) The third contribution on mechanoreception combines the findings of the previous two contributions and explores moving touches and stroke stimuli on the body, as well as their roughness perception in VR. (4) The fourth contribution addresses thermoception where the effects of cold and warm temperatures on the body are investigated within a VR environment. (5) The fifth contribution focuses on proprioception and kinesthesia and examines concepts for kinesthetic actuations that can evoke flexion and extension of body joints. (6) In a further contribution, a novel rapid prototyping platform is presented that considers the specific requirements for haptic actuations of the somatosensory system