The Missile Defense Agency (MDA) propulsion systems are seeking to maintain stringent performance requirements and simultaneously expose materials to severe operating conditions while reducing weight and power consumption while maximizing fast response times. This requires innovative actuation and valve technologies to minimize the response time for fine attitude control and pointing for divert and attitude control systems. MDA is seeking materials and components that demonstrate improvements in producibility and cost reduction for application to solid and liquid propellant divert and attitude control systems (DACS). Specifically, MDA is seeking valve technology with reduced part counts and complexity while achieving very fast response times for valve opening and closing. Very fast valve response is challenging for magnetic devices of any size, but is particularly problematic as size increases due to higher flow rates and spring forces increase to seal-off higher pressures. Limited electrical power will constrain solutions further as coil resistance lower limits are set by the maximum amperage specification. In this research, WASK Engineering, Inc. will apply piezoelectric actuation to the cold gas ACS thruster so as to: 1) enable ACS throttling, yielding proportional control of ACS thrusters and the attendant potential for game changing improvements in sensor pointing, target acquisition and target tracking; 2) eliminate magnetic coils and magnetic materials, resulting in greater operating temperature range through the use of materials with higher temperature capability; 3) eliminate magnetic actuation and the attendant electromagnetic interference (EMI) generated when a high performance magnet is energized; 4) reduce part count, resulting in lower manufacturing cost and potentially higher reliability; and 5) maintain or improve response times previously demonstrated.
Keywords: Valve, Thruster, Acs, Dacs, Propulsion, Fast Response, Piezoelectric, Actuator
