Haptics can enable a direct communication pipeline between the artificial limb and the brain; adding haptic sensory feedback for prosthesis wearers is believed to improve operation without drawing too much of the user's attention. Through neuroplasticity, the brain can become more cognizant of the information delivered through the skin and may eventually interpret it as inherently as other natural senses. In this thesis, a wearable haptic feedback device (WHFD) is developed to communicate prosthesis sensory information. A 14-week, 6-stage, between subjects study was created to investigate the learning trajectory as participants were stimulated with haptic patterns conveying joint proprioception. 37 healthy participants were divided into three groups, with each group assigned a different haptic stimulation method (τ₀, τ₁ or τ₂). 18 participants managed to complete the study within 7–14 sessions, demonstrating that participants were, in fact, learning to interpret the haptic information. Participants in group τ₂ had some advantages in interpreting the haptic information over the others; however, each stimulation method has advantages that can be exploited and hybridized for future models of the WHFD. Learning rates within groups were highly variable and deterred significantly with increasing quantities of simultaneous information. A secondary investigation determined strategies to improve the ability of the haptic actuators to transfer information to the user, which will be employed for future prototypes. Overall, the proposed WHFD is an effective device that can promote greater sensory awareness for wearers of prostheses.
Keywords:
haptic feedback; prosthetics; sensory substitution; sensory augmentation; proprioception