Pintle Actuator for Hypersonic Defense (PAHD)

Electromechanical actuators (EMA) are utilized in every flight and propulsion control system within the Missile Defense System (MDS). High performance actuators for interceptor technologies, including pintle actuators, primarily consist of Brushless Direct Current (BLDC) motors connected to a drivetrain system to produce a linear or rotary output motion. The size, weight, and power output that is achievable with a given EMA largely constrains the maximum deliverable power density for a given mechanical envelope. Technology advances to increase current capacity and electrical conductivity in BLDC motors are needed to increase delivered torque output while improving size, weight, performance and cost. Advances in additive manufacturing, rare-earth permanent magnetic materials, and Copper nanotechnology provide a pathway to significantly improve actuator performance while decreasing cost. Along with BLDC motor components, a large portion of EMA cost is associated with the drivetrain (gearing, rack/pinion), housing components (end bells, sleeves, bearings, sensors, etc.), and the motor controller / software needed to operate the EMA. For pintle actuators, a previously qualified BLDC design is typically combined with a high-temperature drivetrain capable of withstanding the extreme environments of a throttleable solid propulsion DACs. Consideration is then given to how the given design can be thermally protected from the extreme S/TDACS environment. Approaching EMA design from a systems-oriented standpoint would allow incorporating thermal protection (via structural insulators) into a given pintle design at an earlier stage. This approach would decrease EMA cost via parts reduction when also combined with additive manufacturing of other, low-temperature EMA components to save mass. Exo-Atmospheric Technologies, LLC, (EXO), working with our commercialization partner Aerojet Rocketdyne (AJR), proposes to develop a new BLDC motor-based EMA for pintle applications based on a modified COTS BLDC motor that utilizes advanced composite windings with an additively manufactured, low-heat transfer drivetrain coupled to a BLDC motor controller developed by EXO. The Pintle Actuator for Hypersonic Defense (PAHD) will be designed and fabricated in house and bench-top tested to determine suitability for MDA applications. Approved for Public Release | 23-MDA-11635 (9 Nov 23)