SBIR-STTR Award

Greater deployment of helmet-mounted equipment has increased the frequency of neck pain, fatigue, and injury experienced by pilots at high-g, driving the need for a head and neck support system. Most fighter pilots have experienced flight-related neck pain during their career, causing serious ramifications for force readiness. Previously developed solutions are typically passive or one-use devices that cause some additional discomfort or restrict free head movement, leading to very low rates of pilot adoption. Conventional electromagnetic, hydraulic, or pneumatic actuator hardware would enable actively-controlled solutions, but all severely lack the performance needed to achieve an adequately lightweight and responsive system. An effective mitigation for increased neck loads due to helmet-mounted equipment must consider size, weight, power consumption, range of motion of the pilot, and variation in pilot size. Exotendons that employ electroadhesive clutches to activate and deactivate assistance are exceptionally well-suited to the challenge of preventing pilot neck fatigue and injury. The electroadhesive clutch hardware pioneered by ESTAT Actuation is paper-thin, flexible, weighs mere grams, and consumes just Milliwatts of power. Using electroadhesive clutches, the exotendons can be designed to redirect inertial forces during high-g maneuvers from the helmet to the torso, reducing the stress experienced by the neck musculoskeletal system. This 6-month project will focus on customer discovery, exotendon design, and benchtop evaluation of various designs and materials architectures. We will interview end-users and other Air Force Stakeholders using established customer discovery techniques. This feedback will be turned into initial designs that will be iteratively optimized with additional feedback. The exotendon hardware will be validated to TRL 3 in Phase I to demonstrate the performance required to create a full head and neck assistive system in Phase II. Development activities will include testing multiple geometries and exploring multiple electrode/dielectric material combinations as necessary. After completing the design, fabrication, and preliminary benchtop verification of our electroadhesive clutch exotendon component, a test plan will be drafted for execution in Phase II in partnership with AFLCMC/WNU and AFRL. During Phase II the full head and neck assistive system prototype will be constructed and assessed by stakeholder contacts. Given the strong military need to enhance the safety and readiness of the pilots of high-G aircraft, ESTAT has a strong path to achieve a commercially-viable safety solution through Phase I and II development and Phase III acquisition.

This Phase II proposal builds on the successful outcomes of our Phase I project, Lightweight Electroadhesive Exotendon (LEET) for Head and Neck Protection (Contract Agreement # W81XWH22P0039), which focused on the development of exotendon prototypes for reducing acute and chronic neck injury for pilots using helmet mounted equipment. These novel devices use electroadhesive clutches to rapidly transition from a protective mode capable of supporting large inertial loads to a free motion mode which provides full range of motion and freedom of movement to pilots. The prototypes demonstrated a holding force exceeding 134 N, the force needed to attenuate neck loading by 25% or more during a 12-G vertical maneuver. Prototype clutches have undergone more than 500 cycles of use without failure of the electroadhesive materials and have been integrated into a helmet and harness. Lastly, we shaped our Phase II proposal based on the results of 26 customer discovery interviews which revealed the needs of pilots and stakeholders from five branches of the Human Systems Directorate (HSD). Our Phase II effort will transition our TRL3 prototypes to TRL6 and establish a Phase III transition plan. Our four objectives are: evaluation of airworthiness, transitioning to a standalone LEET system, optimization of the LEET control approach, and the development of a Phase III transition strategy. These objectives will be achieved by revising the Phase I prototypes to make them more robust to environmental risk factors. Developing a mobile power and control unit will transition our benchtop prototypes to standalone units. Next, we will subject these prototypes to standard tests of common risk factors including EMI/EMC, temperature, humidity, salt spray, vibration, rapid decompression, and explosive atmosphere. This will demonstrate that the LEET system can withstand the harsh conditions often encountered by Aircrew Flight Equipment (AFE). We will optimize the LEET control strategy and mounting positions of the exotendons via biomechanical simulations in OpenSim. This work will culminate in the completion of four LEET prototypes for manikin testing at Wright-Patterson Air Force Base. This testing will demonstrate the ability of the LEET system to provide protection against neck injury. Lastly, we will construct our Phase III transition plan by developing a relationship with an industry partner. It is our goal to not only demonstrate the capability of our system, but also have a framework in place to transition the resulting TRL6 prototypes to standard Aircrew Flight Equipment.