Enabling Large Space Optics: SAFIR Human and Robotic Development

1. Enabling Large Space Optics:SAFIR Human and Robotic Development Tracey M. Espero Gary L. Bingaman Michael A. Fruhwirth Seth D. Potter tracey.m.espero@boeing.com mobile 714-389-8694

2. Introduction • SAFIR Human and Robotic Development (SHRD) • Single Aperture Far Infra-Red telescope (SAFIR) • Complex and ambitious mission • Considerable expense – need to increase productivity and mission life • Study initiated by the Chief Technologist of NASA’s SMD (Thronson) as part of several systems assessments of options for future large optics; and supported by the Future In-Space Operations (FISO) working group : • Benefits of human and robotic servicing of SAFIR • Architecture elements that would enable such servicing • Commercial applications of in-space servicing • SAFIR and other large space optics are enabled by the exploration architecture in development (Ares V, etc.) • Large apertures in free space are on the horizon, and cost/productivity factors will almost certainly favor servicing including the ability to rescue and repair

3. SAFIR Servicing Background • Key properties which shape servicing requirements: • Operations at Sun-Earth L2 (SE L2) • 10 meter segmented primary aperture operational over wavelengths from 30 to 800 microns • Active/passive thermal control to result in ~ 4 K optics temperatures • Approximate launch date ~2020 • Servicing after the first 5 years of mission life and at each subsequent 5 year interval • Human and robotic roles limited to servicing operations • SHRD builds upon the work of: • SAFIR Vision Mission team study and report • Johnson Space Center exploratory effort on SHRD • Number of references on SAFIR

4. Servicing Considerations • Issues to address • Structural requirements derived from servicing of major elements • Sunshade • Solar panels • Etc. • Tolerance to robotic or human operations in its vicinity • Identifying the systems/subsystems/components to be serviceable • Appropriate servicing methods • Degree of servicing activity/burden placed on the servicing agent • Initial design to accommodate servicing concept • Possible Orbital Replacement Units (ORU) servicing approach • Emphasize accessibility • Consider worksites

5. SHRD Study Approach Quality Functional Deployment (QFD) study conducted to provide an integrated assessment of the servicing operations and define potential architectures • Servicing requirements defined by observatory managers • Main servicing operations • e.g. Maintenance, repair or replacement of the science instruments, sunshade, solar panels, propellant, cryocooler • Servicing functions are the methodology, hardware, and process options that could be employed by the servicing vehicle/observatory combination. • Fulfill the desired servicing operations • e.g. Access to the “cold side” of the observatory to enable instrument replacement • Overall space architecture provides the elements to support the defined servicing operations, and defines location

6. QFD Results • Identifies how servicing requirements are met by specific architectures & elements (blue = best, green = better, yellow = good, red = poor) • High-ranking architectures • Servicing at SE L2 by a resident robotic servicing vehicle • CEV plus telerobotics servicing in a cis-Lunar orbit with a tug transport Both include a cargo transport vehicle

7. Servicing Architectures • Resident robotic servicing vehicle concept at SE L2 • Science instruments placed on the “warm side” of the observatory for accessibility • Sunshade + Instrument removal and replacement supported by a cargo vehicle with replacement ORUs shown • Robotic systems developed for exploration architecture are likely to be adaptable for free-space use Detailed reports available by request

8. Servicing Architectures • CEV with telerobotic capability in cis-Lunar orbit • Least disruption to the nominal observatory operational design for off-site servicing • Performs SAFIR servicing with advanced robotics (no EVA) • Human-in-the-loop decision making possible with telerobotic control from CEV • Cargo vehicle provides replacement sunshade and instruments shown

9. Exploration Enables SHRD Current architecture yields a “better” fit for most SAFIR servicing needs

10. Conclusion SAFIR and missions of its type will likely be too expensive to be used for only one design lifetime and then replaced Exploration architecture in development provides capabilities that enable servicing of observatories such as SAFIR These capabilities should be augmented to allow new observatories to enjoy life extension and enhanced science productivity via servicing

11. Orbital Express Is About to Demonstrate Servicing Technologies Fully autonomous proximity op’s ORU standards and autonomous placement Auto. fluid transfer Robust free flyer capture ‘Soft’ capture & berthing