Andre Garcia

Multimodal urgency coding: auditory, visual, and tactile parameters and their impact on perceived urgency

Through a series of investigations involving different levels of contextual fidelity we developed scales of perceived urgency for several dimensions of the auditory, visual, and tactile modalities. Psychophysical ratings of perceived urgency, annoyance, and acceptability as well as behavioral responses to signals in each modality were obtained and analyzed using Stevens Power Law to allow comparison across modalities. Obtained results and their implications for use as in-vehicle alerts and warnings are discussed.

Individual Differences in Multimodal Waypoint Navigation

Waypoint navigation is a critical task for dismounted soldiers, especially when navigating through novel environments with potential threats. In these dangerous environments, the soldiers should have their “eyes-up” and “ears-out” scanning the environment for critical signals. Current practices for dismounted soldiers include the use of a compass and map or small wearable computer in order to navigate. In this experiment, we compared several modalities and multiple combinations of these modalities in waypoint navigation performance. These modalities include two visual (an egocentric and a geocentric map), 3D spatialized audio, tactile, and the multimodal combinations of each. We also examined individual differences in sense of direction as a potential moderator of display usage. Results provide preliminary evidence that localized 3D audio and haptics navigation aids are an intuitive, efficient, and effective means of waypoint navigation, regardless of sense of direction.

Evaluating the Benefits and Potential Costs of Automation Delegation for Supervisory Control of Multiple UAVs

Previous studies have begun exploring the possibility that “adaptable” automation, in which tasks are delegated to intelligent automation by the user, can preserve the benefits of automation while minimizing its costs. One approach to adaptable automation is the Playbook®interface, which has been used in previous research and has shown performance enhancements as compared to other automation approaches. However, additional investigations are warranted to evaluate both benefits and potential costs of adaptable automation. The present study incorporated a delegation interface into a new display and simulation system, the multiple unmanned aerial vehicle simulator (MUSIM), to allow for flexible control over three unmanned aerial vehicles (UAVs) at three levels of delegation abstraction. Task load was manipulated by increasing the frequency of primary and secondary task events. Additionally, participants experienced an unanticipated event that was not a good fit for the higher levels of delegation abstraction. Treatment of this poor “automation fit” event, termed a “Non-Optimal Play Environment” event (NOPE event), required the use of manual control. Results showed advantages when access to the highest levels of delegation abstraction was provided and as long as operators also had the flexibility to revert to manual control. Performance was better across the two task load conditions and reaction time to respond to the NOPE event was fastest in this condition. The results extend previous findings showing benefits of flexible delegation of tasks to automation using the Playbook interface and suggest that Playbook remains robust even in the face of poor “automation-fit” events.

The Independence and Interdependence of Coacting Observers in Regard to Performance Efficiency, Workload, and Stress in a Vigilance Task:

Objective We investigated performance, workload, and stress in groups of paired observers who performed a vigilance task in a coactive (independent) manner. Background Previous studies have demonstrated that groups of coactive observers detect more signals in a vigilance task than observers working alone. Therefore, the use of such groups might be effective in enhancing signal detection in operational situations. However, concern over appearing less competent than one’s cohort might induce elevated levels of workload and stress in coactive group members and thereby undermine group performance benefits. Accordingly, we performed the initial experiment comparing workload and stress in observers who performed a vigilance task coactively with those of observers who performed the vigilance task alone. Method Observers monitored a video display for collision flight paths in a simulated unmanned aerial vehicle control task. Self-reports of workload and stress were secured via the NASA-Task Load Index and the Dundee Stress State Questionnaire, respectively. Results Groups of coactive observers detected significantly more signals than did single observers. Coacting observers did not differ significantly from those operating by themselves in terms of workload but did in regard to stress; posttask distress was significantly lower for coacting than for single observers. Conclusion Performing a visual vigilance task in a coactive manner with another observer does not elevate workload above that of observers working alone and serves to attenuate the stress associated with vigilance task performance. Application The use of coacting observers could be an effective vehicle for enhancing performance efficiency in operational vigilance.

Visual-Spatial Learning and Training in Collaborative Design in Virtual Environments

This chapter reviews different types of immersive virtual environments (IVE) and discusses the major advantages that these environments can offer in the domain of visual-spatial learning, assessment, and training. Overall, our review indicates that immersion might be one of the most important aspects to be considered in the design of learning and training environments for visual-spatial cognition. Furthermore, we suggest that only immersive virtual environments can provide a unique tool for assessing and training visual-spatial performance that require either the reliance on non-visual cues (motor, vestibular, or proprioceptive) or the use of egocentric frames of references.

Gender Differences in Simulator Sickness in Fixed- versus Rotating-Base Driving Simulator

This experiment compared simulator sickness between males and females as a function of fixed-base versus rotating base platforms. Eight males and eight females drove through two routes in a driving simulator. One route was presented in fixed-base mode and another was presented in motion-base with a .5 to 1 ratio of motion (physical world to virtual world). Routes and fixed versus motion mode were presented in counter- balanced order. Measures of simulator sickness on the Simulator Sickness Questionnaire (Kennedy et al., 1993) were obtained after each route. As predicted, males reported lower levels of simulator sickness than females. A nonsignificant trend for this gender effect to be diminished in the rotating versus stationary condition was observed. Results warrant additional investigation into the potential for motion-based platforms to reduce the incidence and severity of simulator sickness in populations at greater risk of experiencing these negative consequences (i.e., females and older adults).

Team Vigilance The Effects of Co-Action on Workload in Vigilance

Operator vigilance is a vital concern to the Human Factors/Ergonomic community in regard to cockpit monitoring, air-traffic control, border security, baggage inspection, the supervisory control of unmanned aerial vehicles, and the monitoring of anesthesia gauges, among others. Of key interest is the performance of teams of observers because of the reliance of modern operations on good teamwork. Previous literature has examined the efficacy of team vigilance performance by comparing the frequency of target detections by teams in comparison to those obtained by operators working alone. Team performance has consistently exceeded singleoperator performance. The present study replicates this effect and provides the initial experimental investigation of the cost of being a team member. Results indicated that team members worked harder in terms of theta band activity, but reported similar subjective workload values when compared to that of single operators in the performance of a simulated UAV monitoring task.

Comprehension of vibrotactile route guidance cues

Two experiments with 24 participants each evaluated comprehension of vibrotactile route guidance instructions via a tactile seat in a driving simulator. Vibrotactile patterns were presented from an array of 8 tactors arranged in two rows of 4 tactors located in the seat pan. A faster pulse rate and a slower pulse rate as well as four distinct locations on the tactile seat (Front-Left, Front-Right, Back-Left, Back-Right) created 8 different combinations of stimuli. Across all participants, the most consistent interpretation was that the faster pulse rate played from the back two tactors was perceived as an instruction to make the next most immediate turn while a slow pulse rate from the front two tactors was interpreted as a cue directing the user to the direction of the next eventual turn. Results have direct implications for design of effective vibrotactile and multimodal route guidance systems.

Tactile Route Guidance Performance and Preference

We examined performance and preference for tactile route guidance formats. Participants drove a simulated vehicle through counterbalanced pairings of four distinct cities using one of four navigation systems (three tactile and one auditory control). One tactile system used only the pulse rate, the second system used only tactor location, and the third used both pulse rate and location to convey guidance instructions. All navigation systems provided both a preliminary and an immediate cue indicating to take the next most immediate turn. The pulse-rate route guidance system was the most commonly preferred system. Results also indicate that participants’ ability to accurately retrace their route and identify landmarks did not differ across navigation systems. All four systems resulted in equivalent wayfinding performance and support previous literature indicating that tactile guidance systems can effectively support navigation in unfamiliar environments.

Auditory-Spatial Executive Function across Spatial Frames of Reference

An experiment utilizing an auditory-spatial Stroop paradigm was created to assess whether participants are better able to attend to spatial or semantic information across near and far regions of space. Participants were instructed to attend to either the semantic information of a stimulus or identify the location of where the stimulus came from, depending on the condition. The sounds came from speakers that were physically located in either near space (peripersonal region of space) or far space (extrapersonal region of space) and the words were either “near” or “far.” Results indicate that participants in general were quicker at responding to the semantic condition than the location condition. Furthermore, consistent with findings of many other Stroop-like experiments, there was a significant difference between congruent and incongruent trials in both task conditions. The results of this investigation provide additional insight into how people process different types of information across near and far regions of space.