ESPA Based Secondary Payload Orbit Maneuvering System

Busek proposes to develop an integrated propulsion, power, ACS, (ProPACS) system for micro-spacecraft deployed from the ESPA ring secondary payload ports. The standardized ProPACS system integrates the essential elements needed for highly capable micro-spacecraft bus including; 1) 600 W Hall effect thruster system for primary propulsion, 2) Xe cold gas thrusters for propulsive ACS, 3) articulated solar array, batteries and power management and distribution (PMAD) system with steady state power of 700W available to the payload when propulsion is off and 4) an integral structure that supports the payload and a LightBand separation mechanism for the ESPA ring. The ProPACS can provide over 1,800 m/sec deltaV to a 181 kg spacecraft with a 80kg payload. In Phase 1 ProPACS system architecture design was completed and all major components were identified. Mass, power, data budgets were developed and major interfaces were specified. Phase 2 focus will be on the ProPACS elements with lower TRL to achieve system wide TRL6 at the end of the program. The thruster will be advanced to near flight level, two PMAD systems will be evaluated and one selected and the ProPACS integral structure supporting the payload and separation ring will be designed and built.