DSM Phase II NAVY SBIR to design and build a Vertical Linear Accelerator for Human Visual-Vestibular Acuity Testing and Training.
We welcome inquiries into this developing technology and are actively seeking commercial opportunities for this system and/or expansion into additional military platforms.
Motion Requirements: 12ft. stroke, 2Hz freq. response, 1G peak acceleration, 182kg (400lb) total payload, ± 3mm position error, arbitrary waveform capability.
DSM Vertical Linear Accelerator for Vestibular Testing - Full Length Run
(Note: Installation during this phase is in a machine shop; air sounds, etc are from the shop operations)
Vertical Linear Accelerator for Vestibular Testing
Horizontal Air Bearing Test
DYNAMIC STRUCTURES & MATERIALS, LLC
OSD 05-H13 Awarded: 18APR06
Title:Vertical Accelerator for Visual-Vestibular Acuity Testing and Training
Abstract:Military personnel are often subjected to significant amounts of vertical acceleration while carrying out their duties. This acceleration can interfere with the person's ability to perform their required tasks due to the vestibular ocular reflexes caused by viewing a platform fixed display. Also, it has been shown in literature that repeated exposure to this type of motion can desensitize a person from these natural reflexes. The development of a vertical lift mechanism and training station that can provide an important test/measurement/training function is proposed to provide the basis of a tool for testing and desensitizing of military individuals. Proposed for the test station is a vertical linear stage directly driven via high force linear motor technology. The carriage of this stage will include a chair and restraint system as well as a projection device for displaying visual optotypes. The system will include a fail safe brake system and all necessary redundancies to ensure the safety of the human subject.
Topic Num: OSD05-H13 (OSD)
Title: Vertical Linear Accelerator for Dynamic Visual-Vestibular Acuity Health Status Evaluation and Desensitization Training
Research & Technical Areas: Biomedical
Objective: To provide a human-rated linear motion device with chair mounted projection system capable of delivering visual acuity screening stimuli during vertical oscillations.
Description: Several military platforms induce significant amounts of vertical linear acceleration. Functional performance on these service platforms requires the visual suppression of vestibular (inner ear) ocular reflexes in order to view platform-fixed displays. Undetected visual-vestibular pathology or injury during deployment increases risk of spatial disorientation related mishaps, and/or decreased performance due to motion sickness related symptoms. The ability to provide adequate health status evaluation of this important function has been traditionally limited to subjective ratings by non-specialist health care professionals. A computer-controlled motion device that can induce vertical linear motion will provide more systematic and sensitive heath status evaluation that can be deployed and conducted by non-specialists. The incorporation of visual acuity tasks will ensure the metrics will provide functionally relevant assessment of risk. In addition to screening exams, this vertical motion device can be employed as a rehabilitation tool. Evidence for this comes from the Royal Air Force who report repeated exposures to vertical linear motion as a successful desensitization tool for chronically motion sick aircrew.
PHASE I: The proposal for Phase I should identify the review of different linear motion technologies that could provide a field-based vertical motion device covering functionally relevant frequency (0.1-2.0 Hz) and amplitude (0.1 – 1G) range. The Phase I study should also include the development of a lightweight visual projection device that can be mounted to the vertical oscillator and provide visual optotypes (e.g., Landolt C) covering a wide range of sizes (logMAR -0.3 to 1 in 0.1 steps) at near (0.5m) viewing distances. During Phase I, the visual projection system should be prototyped and tested with existing motion devices to evaluate both acuity and desensitization protocols.
PHASE II: In Phase II, the vertical motion device development should be completed following critical design reviews with the technical staff. This device will undergo feasibility testing for both screening and desensitization applications. To accomplish this, the device will be installed at a military base with other state-of-the-art vestibular test capabilities and with access to military personnel undergoing a motion sickness related desensitization program.
PHASE III: During Phase III, the private sector applications of this device will be explored with installation of a second unit in a neurotology clinic where diagnostic performance can be compared with other comprehensive balance function screening tools, and the device can be implemented as a tool for vertigo and motion sickness desensitization.
References:  Bagshaw M, Stott JR. The desensitisation of chronically motion sick aircrew in the Royal Air Force. Aviat Space Environ Med 1985;56(12):1144-51.  Demer JL, Honrubia V, Baloh RW. Dynamic visual acuity: a test for oscillopsia and vestibulo-ocular reflex function. American Journal of Otology 1994;15(3):340-7.  Golding JF, Kerguelen M. A comparison of the nauseogenic potential of low-frequency vertical versus horizontal linear oscillation. Aviat Space Environ Med 1992;63(6):491-7.  Guedry FE, Jr., Benson AJ, Moore HJ. Influence of a visual display and frequency of whole-body angular oscillation on incidence of motion sickness. Aviat Space Environ Med 1982;53(6):564-9.  Schmal F, Kunz R, Stoll W. The vertical linear vestibulo-ocular reflex in patients with a hyperactive response during horizontal angular acceleration. Acta Otolaryngol 2003;123(5):606-11.
Keywords: vestibular, acuity, balance, otolith, assessment