Model-based engineering (MBE) in industry is on the rise. However, improvements are still needed on the oversight and management of MBE efforts. Frequently, program managers and high level decision makers do not have background in MBE to understand models, the value the models are providing, and if they are successfully achieving their MBE goals. To address these concerns in our previous research we developed a rating scale for models, called Model Assurance Levels (MALs). A MAL level is used to concisely express the assurance the model is providing to the program, as well as, risks associated with the model. However, for MAL level to be effective and meaningful, they need to be consistently determined regardless of who is performing the assessment. Therefore, this paper describes a quantitative and repeatable approach for computing MAL levels for software models.

Space flight software continues to experience exponential growth as functionality migrates from hardware to software. The resulting complexity of these mission critical systems demands new approaches to software systems engineering in order to effectively manage the development efforts and ensure that reliability is not compromised. Model-based systems/software engineering (MBE) approaches present attractive solutions to address the size and complexity through abstraction and analytical models. However, there are many challenges that must be addressed before MBE approaches can be effectively adopted on a large scale across an entire system. In this paper, we discuss some of the key motivators and challenges based on our experiences with flight software programs employing elements of MBE.

Software design patterns are best practice solutions to common software problems. However, applying design patterns in practice can be difficult since design pattern descriptions are general and can be applied at multiple levels of abstraction. In order to address the aforementioned issue, this research focuses on creating a systematic approach to designing domain specific distributed, real-time and embedded (DRE) software from software architectural design patterns. To address variability across a DRE domain, software product line concepts are used to categorize and organize the features and design patterns. The software architectures produced are also validated through design time simulation. This research is applied and validated using the space flight software (FSW) domain.