This study examined whether a powered ankle exoskeleton affected street crossing decisions and perceived mental workload of novice users without mobility limitations at a simulated traffic intersection.
Background
Exoskeletons are wearable mobility devices that can impact physical and cognitive performance. Exoskeleton commercialization for the public necessitates evaluations into how these systems influence novices’ cognitive reasoning and directed attention in urban environments.
Methods
Participants (n = 20) made street crossing decisions with and without the exoskeleton. Participants walked through a simulated city using a self-paced treadmill and decided whether to cross the street at prespecified distances from the intersection. Cognitive workload perception was measured using the NASA-TLX survey.
Results
No significant effects of the exoskeleton on street crossing decisions were observed. Rather, data indicated significant reductions in decisions to cross as distance from the intersection increased and with vehicle presence at the intersection. Cognitive workload scores marginally worsened when wearing the exoskeleton.
Conclusion
Street crossing decisions were unaffected, but exoskeletons can influence perceived mental workload. These results highlight the importance of designing wearable systems that align with both physical and cognitive task demands. Future studies should incorporate different exoskeletons, tasks, and user groups to determine how these factors influence task performance.
Application
Understanding the interaction between exoskeletons and novice user cognitions can support the development of exoskeletons that provide sufficient physical support without impeding the mental processes needed for their safe and efficient operation. Researchers can also utilize similar procedures to evaluate alternate exoskeleton designs for urban mobility decision making.
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