1-D Manual Tracing Based on a High Density Haptic Stimulation Grid - a Pilot Effort

Lower limb amputees lack the neurological pathways needed for perception of how their prosthetic limbs are interacting with the environment, leading to a lack of confidence in their devices and reduced balancing capabilities. Sensory substitution methods, such as vibrotactile and electrotactile feedback applied to unaffected body segments offer a potential way to restore some of the lost information pathways. While high resolution haptic stimulation grids have become commercially available, few studies have tried to make use of these devices to provide more intuitive sensory substitution methods. This study developed an encoding approach, which is based on the illusory "phantom actuator" phenomenon, to convert 1-D position information to a wearer through a bHaptics Tactsuit. By evaluating performance of 1-D manual tracking task among 14 participants under the proposed approach and a traditional amplitude modulation approach, we demonstrated an improvement of velocity tracing accuracy (p=0.0375) with the proposed approach, although the proposed approach did not lead to significant improvement in the position tracing accuracy.