Session
Technical Session V: From Earth to Orbit
Abstract
Advances over the past decade in highly reliable commercial electronics, miniaturization techniques, and materials have enabled progressively smaller satellites to provide important scientific and military capability. Access to space, however, continues to be one of the greatest barriers to executing low-cost missions. Capitalizing on significant, otherwise unused launch vehicle (LV) volume and lift mass capability, many developers now seek accommodation as either a secondary payload with some measure of mission/orbit influence (and corresponding cost contribution), or more typically as truly “opportunistic” piggyback/tertiary rideshares. Among the recent leaders in this endeavor are CubeSats, the system class canonically defined as single unit (1U) spacecraft, with typical configurations being developed by many organizations today aggregating three or even six “U” to afford greater mass/volume provision for components. Another popular small satellite class being launched in secondary manifest configurations is the EELV Secondary Payload Adapter (ESPA). Through launches of these rideshare payloads, confidence has been established that they could be safely and readily incorporated into the LV and mission plan without impact to the primary payload. Catalyzed by these successes in dramatically lowering the cost and programmatic barriers to space access, there is growing global interest to find further ways to increase small satellite launch accommodation to quantities well in excess of 10 free-flyer deployments to further leverage unused capacity, support multiple mission partners, and enable the population of constellations. In reflection of this challenge, in early 2011 JHU/APL initiated an internal assessment and investigation of prevailing market solutions for manifesting small satellites as either primary, secondary, or tertiary payloads on a broad variety of current and near-term launch vehicle solutions. Through a combination of top-down analysis and bottoms-up design activities, it was determined that there was a fundamentally un-served niche between 3-6U CubeSats and ESPA-class small satellites, the “Express” mission class, that corresponds to a space vehicle of approximately 20-50 kg and a stowed size of 88,000 cm3. To address these requirements, JHU/APL has developed and built a unique flexible adapter system that can readily integrate with multiple LVs in numerous configurations. While accessing the same low-cost rideshare paradigm as CubeSats, the Express mission class affords far greater utilization of COTS components for reduced program development cost/risk, makes possible the capability for dramatically more system resources (e.g., power generation), and if required, enables integration of propulsion solutions for true orbit flexibility without over-compromising payload SWaP allocation. In this paper we will expand upon analysis findings, associated requirements, expected space vehicle provisions, technical details of the adapter system design, prototype hardware development, and results from qualification testing.
Presentation Slides
A Flexible Rideshare Adapter System to Increase Space Access for “Express” Class 20-50 kg Small Satellite Missions
Advances over the past decade in highly reliable commercial electronics, miniaturization techniques, and materials have enabled progressively smaller satellites to provide important scientific and military capability. Access to space, however, continues to be one of the greatest barriers to executing low-cost missions. Capitalizing on significant, otherwise unused launch vehicle (LV) volume and lift mass capability, many developers now seek accommodation as either a secondary payload with some measure of mission/orbit influence (and corresponding cost contribution), or more typically as truly “opportunistic” piggyback/tertiary rideshares. Among the recent leaders in this endeavor are CubeSats, the system class canonically defined as single unit (1U) spacecraft, with typical configurations being developed by many organizations today aggregating three or even six “U” to afford greater mass/volume provision for components. Another popular small satellite class being launched in secondary manifest configurations is the EELV Secondary Payload Adapter (ESPA). Through launches of these rideshare payloads, confidence has been established that they could be safely and readily incorporated into the LV and mission plan without impact to the primary payload. Catalyzed by these successes in dramatically lowering the cost and programmatic barriers to space access, there is growing global interest to find further ways to increase small satellite launch accommodation to quantities well in excess of 10 free-flyer deployments to further leverage unused capacity, support multiple mission partners, and enable the population of constellations. In reflection of this challenge, in early 2011 JHU/APL initiated an internal assessment and investigation of prevailing market solutions for manifesting small satellites as either primary, secondary, or tertiary payloads on a broad variety of current and near-term launch vehicle solutions. Through a combination of top-down analysis and bottoms-up design activities, it was determined that there was a fundamentally un-served niche between 3-6U CubeSats and ESPA-class small satellites, the “Express” mission class, that corresponds to a space vehicle of approximately 20-50 kg and a stowed size of 88,000 cm3. To address these requirements, JHU/APL has developed and built a unique flexible adapter system that can readily integrate with multiple LVs in numerous configurations. While accessing the same low-cost rideshare paradigm as CubeSats, the Express mission class affords far greater utilization of COTS components for reduced program development cost/risk, makes possible the capability for dramatically more system resources (e.g., power generation), and if required, enables integration of propulsion solutions for true orbit flexibility without over-compromising payload SWaP allocation. In this paper we will expand upon analysis findings, associated requirements, expected space vehicle provisions, technical details of the adapter system design, prototype hardware development, and results from qualification testing.
