Gunners, patrol personnel, cooks, medics and other Soldiers who wear helmets for long periods of time could get much needed head and neck relief from a revolutionary device developed by U.S. Army Research Laboratory researchers, a new study found.
The Vertical Load Offset System—or VLOS, a prototype exoskeletal device designed to displace the static load of the helmet onto the shoulders, proved in recent studies to reduce apparent strain overall on a Soldier’s head and neck. Some Soldiers reported both the sensation of lighter head-borne weight and more helmet stability. Achieving these results—given the dynamic movement of the head in combination with helmets loaded with equipment such as night vision devices, batteries and other equipment—is a major step forward, researchers said.
Soldiers at Aberdeen Proving Ground, Md., reported these and other immediate benefits of the archetype during a week-long human-factors evaluation conducted earlier this summer on the Soldier Performance Equipment Advanced Research (SPEAR) obstacle course and at the SPEAR Biomechanics Laboratory.
Dr. Shawn Walsh, principal investigator for VLOS concept development, said VLOS potentially could “serve as a technology solution that makes helmets with more ballistic coverage and head-borne electronic hardware more tolerable.”
“This research is allowing us to dissolve the boundary between head protection and torso body armor, which historically have been discrete, disconnected systems. VLOS has enabled us to move into exploring new modes of Soldier protection research; it could represent a totally new piece of equipment not found in any Soldier ensemble issued to date. ARL research is helping break down this technology barrier,” he said.
The concept was initiated by ARL as part of a broader, higher risk mission effort to explore new modes of Soldier protection. Early requirements suggested that the device needed to be lightweight, minimally intrusive and had to be retrofit to current helmet and body armor systems. Walsh stated, “The dynamics of the head’s movement relative to the shoulders made this design concept especially challenging.”
The field study looked at ways to get Soldiers to actually wear such a device.
Bill Harper, a research psychologist with ARL’s Human Research and Engineering Directorate, said the study required, “Soldiers ages 30-39 to also traverse 1.5 miles along a cross country course before engaging in another series of 20-meter sprints, 10-meter crawls, weapons handling and a ladder climb.” Weapon compatibility was also examined by having Soldiers sight an M4 carbine with M68 sight in the standing, kneeling and prone-firing positions; and sight an M240B medium machine gun through M145 machine gun optic in the prone-firing position.
As part of the study, Soldiers also performed range of motion tasks in HRED’s Biomechanics Laboratory. These trials were performed with and without the VLOS system so that researchers could determine if the VLOS had any negative effects on the ability of Soldiers to look right, left, up or down. For each Soldier, the experimental trials took about six and a half hours to complete.
“The device has been designed to offset the load, while still providing full unencumbered motion to the head and neck, enabling the Soldier to have the same level of maneuverability, while easing the strain to the neck due to the weight of the Personal Protective Equipment. This concept may enable higher levels of protection through use of nonconventional materials for head protection (ceramics or other higher areal density protection materials), by reducing the load on the head and neck and transferring this load to the shoulders,” said Harper, the principal investigator of the evaluation.
He said Soldier feedback helps “guide further refinement of the VLOS concept, and enhance user acceptance as the technology readiness of the device matures.”
ARL teamed with Creative Engineering LLC, based out of Bronxville, N.Y., to “solve this impossible problem” by combining innovative design concepts and engineering rigor to create VLOS from CNC machined aluminum parts with fiberglass flex arms and custom molded carbon fiber.