Constellation Program Contributions
The Constellation Program (CxP) follows a "system-of-systems" organizational approach where efforts are horizontally and vertically organized and integrated. Program-level activities are broad in scope and encompass the development of program-wide policy and definition of high-level requirements across the end-to-end architecture. Moving down through level-2 (functional specification area) and level-3 (project area), the scope becomes more focused on specific elements in the overall architecture and then down into their individual systems and subsystems. Goddard Space Flight Center (GSFC) supports Constellation at each of these levels.
Exploration Systems Projects (ESP) contributions to CxP include:
Unpressurized Cargo (UPC):
Institution/Infrastructure:
Constellation Level-2:
- Systems Engineering and Integration (SE&I)
- Safety, Reliability and Quality Assurance (SR&QA)
- Distributed System Integrated Lab Communications Adapter Set (DSILCAS)
- Electronic, Electrical and Electromechanical (EEE) Parts
Constellation Level-3:
- Crew Exploration Vehicle (CEV) Project Orion
- Mission Operations Project
- Lunar Lander Project
- Lunar Surface Systems Project
- Extra-vehicular Activity (EVA) Project
UPC-Architecture Operations Concept and Requirements
GSFC has been assigned the leadership role for UPC under the Constellation Program. "Unpressurized" refers to the portion of the spacecraft that is outside of the environmentally-controlled section that the crew occupies. GSFC has a long heritage of providing stakeholders with rapid access to space for secondary payloads and will build on its experience and reputation as it manages the integration of UPC into the Constellation architecture.
During the Space Shuttle Program, Goddard managed payloads for the Shuttle Small Payloads Project (SSPP). In this role, GSFC facilitated relationships between payload providers and the Shuttle program, acting as the primary interface for all mission integration activities. While the specific integration process and role of GSFC for Constellation is in formulation, Goddard remains dedicated to ensuring the safe and successful flight of secondary payloads, including cargo to the International Space Station (ISS) and the moon.
UPC-Orion
This concept depicts the Orion service module with an unpressurized cargo carrier.
In order to reduce life cycle costs, the Crew Exploration Vehicle (CEV), Orion, is being designed as a flexible spacecraft that supports both missions to Low-Earth orbit (LEO) and the Moon. Since Orion must accommodate additional propellant and other mission critical resources to support longer duration flights to the Moon, excess capacity is available to LEO missions that can be used to deliver secondary payloads such as cargo, experiments, and satellites to space. Lunar mission modes will also be able to accommodate secondary payloads, but with a more limited capacity.
While the UPC capability is still in formulation, it is the expressed goal of the Constellation program that the capability has several different configurations, permitting Orion to accommodate a wide variety of secondary users. The three mission modes, that have been identified for UPC include:
- Extraction Mode – This is the primary mode and will enable the Space Station’s robotic arm to extract cargo for transfer to the International Space Station (ISS) once the Orion vehicle is docked.
- Fixed Pallet Mode – This mode will accommodate fixed cargo and provides for a wide range of instrumentation to be permanently fixed to the vehicle. Examples of cargo for this mode include Development Flight Instrumentation (DFI) or scientific sensors for sky surveys. In this mode, users will be capable of deploying sensors for enhanced performance (e.g., extension of a boom for magnetometer readings.)
- Ejection Mode - This mode will enable the Orion vehicle to deliver small satellites into low Earth orbit via a safe deployment mechanism previously used on the Space Shuttle.
UPC-Lunar
The UPC-Lunar activity is currently focusing on the definition of design and engineering requirements that dictate how unpressurized cargo will be transported to the lunar surface by the nation’s next lunar lander, Altair. Currently the lunar architecture is still in conceptual development. More details will be provided as results are released.
Institution/Infrastructure Contributions
Low Impact Docking System (LIDS)
The picture is of GSFC/WFF fabricated piece parts for the LIDS Risk Reduction Unit – Drawing 7, 2007.
Constellation flight elements, like Orion, are significantly less massive than the Space Shuttle, requiring a newly designed, more sensitive docking mechanism. LIDS has been designed to support the new vehicles across the Constellation architecture and is similar to, but not compatible with, current system used on the International Space Station (ISS).
The LIDS is being manufactured by a consortium of fabrication teams across NASA. A key member of this group is based at GSFC's Wallops Flight Facility (WFF), Wallops Island, Virginia. This team supports the fabrication and machining of high-precision piece parts needed to construct this next-generation docking adaptor for Constellation.
Mission Navigation
The Johnson Space Center – GSFC relationship, in the area of navigation and tracking, dates back to the earliest days of human spaceflight with GSFC serving as the backup mission control operations facility for the primary control center located in Houston, Texas. This integrated team works together to plan future facility upgrades and conduct work-exchange programs intended to integrate this diverse team.
The GSFC Mission Navigation group participates in the definition of tracking and navigation systems that will be required by the new Constellation program vehicles, conducting mission operations to the Space Station, the Moon, and Mars.
Areas where the GSFC Mission Navigation team is contributing include:
- Orion Communications & Tracking (C&T) trade studies
- S-band Transponder Specification development
- System and subsystem design reviews
- Lunar Reconnaissance Orbiter (LRO) worker exchange program.
Systems Engineering and Integration (SE&I)
The Constellation SE&I Office is chartered with executing the systems-based engineering activities that are required to define and integrate the level-2 mission support requirements for the Constellation architecture. The approach is designed to ensure the successful integration of NASA’s systems with an emphasis on safety, increased performance, and cost reduction. SE&I is an area within the CxP where ESP is providing significant contributions. Efforts include participation on several System Integration Groups (SIGs), examining technical areas such as:
- Computer Systems Interoperability (CSI) has been focusing on next-generation methods for communication and data sharing across all the flight and ground systems
- Integrated Loads, Structures, and Mechanisms (ILSM) performed a vibro-acoustic assessment of the Orion Command Module
- Flight Performance (FP) has been involved with defining requirements involving aerodynamics and aerothermodynamics, aborts, trajectory design, mass properties, propulsion, and integrated guidance navigation and control (GN&C).
As part of the SE&I effort, ESP also has a team focused on Verification & Validation, supporting CxP through the System Requirements Review (SRR) in November 2006, as well as, participating in Interface Requirements Document (IRD) development and Constellation Architecture Requirements Document (CARD) updates. Additionally, this team has the lead in defining the end-to-end system testing strategy for the nationwide Constellation team.
Safety, Reliability, and Quality Assurance (SR&QA)
SR&QA encompasses activities that contribute to ensuring the highest possibility of mission success. One of these disciplines is software assurance, focusing on the processes and procedures that will ensure that software, across the Constellation architecture, functions reliably and safely to minimize potential risks associated with loss of life or the mission.
This group within ESP is engaged in activities that are broad in scope and support the development of program-wide policy and definition of high-level requirements. In the area of software assurance, ESP is involved in a wide range of activities, such as influencing designs, acquisition approaches, fabrication plans, and risk management. The team continues to work closely with engineering early in the development process, focusing on key issues such as software safety; testing and evaluation; software probabilistic risk modeling; and ultra-reliability at venues including program-level boards, panels, symposia/working group meetings as well as flight hardware reviews.
Distributed System Integrated Lab Communications Adaptor Set (DSILCAS)
The DSILCAS effort consists of the development of a series of three prototype systems that will be used to promote interoperability and communications between the various Constellation elements. System compatibility across the entire Constellation architecture, as well as, the space station is critical to the success of the program. The DSILCAS work will ensure that all of the various elements from ground systems to crew vehicles are fully interoperable early on in the development phases.
The first of these systems are prototypes of the communications adapters that will be used by the elements of the program, such as Orion, the Crew Launch Vehicle (CLV), Ares, the International Space Station (ISS), the Mission Control Center, and the Launch Control Center. These prototypes are intended to ensure that the different spacecraft, launch vehicles, and ground systems will all be able to communicate using standard protocols and interfaces. The second system to be developed is an interface unit to connect the different vehicle systems together for remote testing. This unit will support early integration and system checkout of the various elements. The third and final system to be delivered in early 2009 is a test set for Orion, CLV, and ISS communications units. This system is to be the “gold standard” which will be used to validate each vendor’s implementations of the communications protocols.
The DSILCAS team at Goddard is supporting the Constellation program through the development of all three systems for use in the Test and Verification (T&V) effort of Constellation. Constellation program management, along with Systems Engineering and Integration (SE&I) organization, view this early prototyping as one of the keys to program success and have entrusted GSFC to complete the effort.
Electronic, Electrical,and Electromechanical (EEE) Parts
EEE Parts management on the Constellation Program ensures that each project will have access to the most appropriate and highest quality parts for each application. It will establish a uniform system for selecting, de-rating, applying, testing, tracking, and performing failure analyses on EEE parts targeted for use across the Constellation architecture.
GSFC has been given responsibility for chairing the Executive Parts Review Board (EPRB) and working closely with the Level 3 EEE Parts Managers to ensure compliance. It provides leadership in top-level decision making processes that have been elevated to Level 2 from the Level 3 Parts Control Boards. The EPRB works closely with other governing entities such as the NASA Engineering Safety Center, contracting officers, Safety and Mission Assurance, and Independent Verification and Validation to ensure consistent compliance.
One of the other key functions of the EPRB is providing EEE Parts Subject Matter Experts (SME) for leadership roles in investigations of EEE Parts problems affecting more than any one Project/System. SMEs also participate in the development of new technology and EEE parts design, test and manufacturing, as well as, space flight qualification of new parts.
Orion Engineering
This is an artist's depiction of an exploded view of Orion. Photo credit: Lockheed Martin Corp.
Orion, also known as the Crew Exploration Vehicle (CEV), will take astronauts into space after the retirement of the Space Shuttle. ESP’s Orion Engineering Group contributes to several key areas of the Orion acquisition effort spanning development of the radio frequency (RF) subsystem and radiation analysis and parts testing.
The engineering team provides direct support to the CEV Project for a number of technical areas encompassing the S-band and Ka-band communications elements for Orion including antenna coverage analysis, communications link margins, RF interference assessment, and spacecraft tracking requirements. Support includes participation in overall architecture definition for the subsystem, review of various Constellation documents, and reviews of action items, as well as, subsystem and component technical specifications.
New satellite measurements for environmental radiation levels in space are being used to update models of radiation hazards that crew and hardware are likely to encounter. In addition, requirements for performance of radiation-sensitive components under consideration for use across the Constellation architecture are being reviewed in order to minimize risks of radiation-induced performance anomalies.
Mission Operations
ESP’s Mission Operations group supports many areas of Constellation operations, including both ground and lunar surface operations and their associated development activities. These efforts include systems engineering, functional analysis, operations modeling, document development, “road mapping”, and consulting for both ground and surface operations of Constellation’s lunar phase.
The ESP Mission Operations team led the effort to provide operations requirements to the Lunar Mapping and Modeling Project (LMMP) to guide the development of mapping and modeling products that will be used in all aspects of the planning, construction, testing, and operation of the lunar outpost.
The task is presently focusing on a functional analysis for the Baseline Operations Plan for ground operations of Orion missions to the International Space Station (ISS); however, the team is also contributing to lunar surface operations planning, as well as, looking for additional opportunities to make meaningful contributions to the Constellation architecture in other areas such as unpressurized cargo.
Lunar Lander
Artist's rendition of a concept lunar lander
The Altair Project at JSC is the focus for building the nation’s next generation lunar lander. ESP supports the Altair nationwide team through systems engineering efforts and avionics development, as well as, flight software development. Goddard has had a major role in development of a minimum functional avionics architecture and flight software plan for Lunar Design Analysis Cycles (LDACs). LDACs are Constellation’s forums for developing the system specifications and requirements that will guide the development of the lunar lander. GSFC has supported the process in LDAC-1, LDAC-2, and will continue to support the development in LDAC-3.
The Altair Effort consists of developing a baseline design that supports three reference missions. The first reference mission is a crewed sortie mission, reminiscent of Apollo, where astronauts land on the moon perform extravehicular activities and return after about a week. The second reference mission is a crewed outpost mission where astronauts land on the moon and stay for long durations at a lunar outpost. The third reference mission is a robotic cargo mission that carries habitation modules and lunar surface systems to the moon. Goddard is also participating in the effort to define Altair system requirements and document requirements traceability in Cradle, an engineering requirements management system. Goddard is expected to take over as the avionics lead in the near future and is looking for additional areas to apply its proficiencies in robotic spacecraft development
