title: Defining soldier equipment trade space: load effects on combat marksmanship and perception-action coupling.
abstract: Soldier equipment compromises task performance as temporal constraints during critical situations and load increase inertial and interactive forces during movement. Methods are necessary to optimise equipment that relate task performance to underlying coordination and perception-action coupling. Employing ecological task analysis and methods from dynamical systems theory, equipment load and coordination was examined during two sub-tasks embedded in combat performance, threat discrimination and dynamic marksmanship. Perception-action coupling was degraded with load during threat discrimination, leading to delays in functional reaction time. Reduced speed and accuracy during dynamic marksmanship under load was related to disrupted segmental coordination and adaptability during postural transitions between targets. These results show how reduced performance under load relates to coordination changes and perception-action coupling. These changes in functional capability are directly related to soldier survivability in combat. The methods employed may aid equipment design towards more optimised performance by modifying equipment or its distribution on humans.
authors.affiliation: a Sensory-Motor Control Lab, Kinesiology Department , University of Massachusetts , Totman Gymnasium, 25 Eastman Lane, Amherst , MA 01003 , USA.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Palmer
authors.forename: Carol
authors.initials: C
authors.lastname: Bigelow
authors.forename: Richard E A
authors.initials: RE
authors.lastname: Van Emmerik
mesh_terms: D000328:Adult; D004192:Discrimination, Psychological; D004867:Equipment Design; D006804:Ergonomics; D006801:Humans; D008297:Male; D008889:Military Personnel; D009048:Motor Skills; D010465:Perception; D011930:Reaction Time; D013647:Task Performance and Analysis; D014481:United States; D016474:Weight-Bearing