Characterization Of Precision And Accuracy For Combined Visual And Haptic Localization

Abstract

This paper describes a combined visual and haptic localization experiment that addresses the area of multi-modal cueing. The aim of the present investigation is to characterize precision and accuracy of tactile cue-ing in the peri-personal space (PPS), the space around the body in which sensory information is perceived as meaningful (Ref. 1). Outcomes of the unimodal (visual and haptic) and multi-modal (combined visual-haptic) localizations are used to make predictions about the multimodal integrative phenomenon. In the localization experiment, participants are presented with visual, haptic, or multimodal target cues using the body-centered reference frame and are instructed to indicate the corresponding hypothetical target location in space using a mouse pointer in an open-loop feedback condition. Results of the study revealed that the visual and haptic spaces are characterized differently in terms of localization performance, providing important considerations for the transformation of each when combining them into a unified percept. The results reaffirmed many well known radial characteristics of the visual receptive field with respect to localization, and identified a nonlin-ear pattern of performance across the haptic receptive field that was largely influenced by the midline of the center of the torso and each side of the cutaneous region. Importantly, when combined, bimodal localization was at least as precise as the most reliable unimodal source over the entire tested region, and significantly more accurate for signals located in regions outside of the direct field of view. These results will help inform the development of future human-machine interfaces implementing haptic feedback mechanisms, specifically with respect to multisensory integration. In the context of pilot performance, haptic localization can have sev-eral benefits including enhanced situational awareness, improved spatial orientation, reduced cognitive load, enhanced training and skill development, and increased safety and error prevention. These benefits can be applied to future systems for safer aircraft handling by helping overcome visual illusions and discrepancies between visual and vestibular sensory channels, especially in degraded visual environments.