// NASA BREAKING NEWS — SPAZIO & SCIENZA
Integrating Model-Based Systems Engineering and Fault Management to Enable Autonomous Space Missions
Fully autonomous space mission operations require the ability to detect faults and compensate for them without human intervention. To address this challenge and provide model-based support for system design and operations, it is important to connect fault management (FM) and model-based systems engineering (MBSE). This approach was successfully demonstrated with the model-based generation of a failure modes and effects analysis and fault trees using NASA’s HelioSwarm mission early design information.
As NASA strives to push the boundaries of space travel with the Artemis program and the agency’s upcoming deep-space science missions, increased system autonomy and resiliency have inevitably become key technology needs. Autonomous operations require fault management (FM) software to detect issues that occur in space so they can be mitigated automatically without human intervention. Designing autonomous missions requires a multi-disciplinary approach that connects FM with the model-based systems engineering (MBSE) approach used in mission design to ensure that resilient, fault-tolerant systems are architected, modeled, and integrated during the design phase.
To address this need, NASA awarded a Phase II Small Business Innovation Research (SBIR) contract to Qualtech Systems Inc. (QSI) for development of FM capabilities and enhancements to its commercially available toolset, TEAMS® (a product that resulted from commercialization of the company’s earlier NASA-sponsored SBIR work), to support HelioSwarm and other NASA heliophysics missions.
One of the most important tasks in this effort was to connect system health management (SHM) and FM to the systems engineering (SE) process. Together, SHM/FM consists of a set of mechanisms that ensure that mission goals are achieved by preventing failures from occurring, or detecting and then mitigating them if they do occur. The SE process coordinates, cross-checks, and integrates system elements to achieve mission goals and is integral during the design, specification, and verification and validation (V&V) of systems. NASA often employs a model-based approach for its SE process, using Systems Modeling Language (SysML) as the framework.
Despite their inherently close relationship to SE in practice, SHM/FM practices have typically not been tightly integrated with SE. Often, SHM/FM is incorporated only after a nominal system is designed, which essentially makes SHM/FM a bandage fix for problems after they occur, without considering how issues might have been prevented. In addition, SE and SHM/FM often involve separate sets of subject matter experts with stove-piped knowledge repositories. This situation can lead to use of modeling methodologies and analyses processes that yield inconsistent results, and can potentially result in inefficiencies throughout the mission life cycle.
This NASA-funded QSI team’s approach integrates SHM/FM directly within the MBSE process from the beginning of a project. This method enables the FM design to be evaluated in an operational context by showing how the SHM/FM schemes mitigate the effects of simulated component-level physical and functional failures. This technique also facilitates trade studies to evaluate the merits of various FM architectures during the design phase.
Under this SBIR effort, QSI worked with the SysML v2 Submission Team (SST) — an assorted group of end users, vendors, academics, and government liaisons involved in the development of specifications for SysML v2, which is the latest iteration of SysML. The QSI team incorporated FM concepts and modeling standards into SysML v2, then they demonstrated how SysML v2 models could translate to the failure space models produced by the QSI toolset.
This capability enables systems engineers to use QSI’s commercial modeling tool set andanalyze the FM aspects of a system design captured in SysML v2. By capturing the causes and impacts of failures, QSI’s toolset enables mission designers to perform Fa