Book Image

Agile Model-Based Systems Engineering Cookbook Second Edition - Second Edition

By : Dr. Bruce Powel Douglass
Book Image

Agile Model-Based Systems Engineering Cookbook Second Edition - Second Edition

By: Dr. Bruce Powel Douglass

Overview of this book

Agile MBSE can help organizations manage change while ensuring system correctness and meeting customers’ needs. But deployment challenges have changed since our first edition. The Agile Model-Based Systems Engineering Cookbook’s second edition focuses on workflows – or recipes – that will help MBSE practitioners and team leaders address practical situations that are part of deploying MBSE as part of an agile development process across the enterprise. In this 2nd edition, the Cameo MagicDraw Systems Modeler tool – the most popular tool for MBSE – is used in examples (models are downloadable by readers). Written by a world-renowned expert in MBSE, this book will take you through systems engineering workflows in the Cameo Systems Modeler SysML modeling tool and show you how they can be used with an agile and model-based approach. You’ll start with the key concepts of agile methods for systems engineering. Next, each recipe will take you through initiating a project, outlining stakeholder needs, defining and analyzing system requirements, specifying system architecture, performing model-based engineering trade studies, all the way to handling systems specifications off to downstream engineering. By the end of this MBSE book, you’ll learn how to implement systems engineering workflows and create systems engineering models.
Table of Contents (9 chapters)
6
Other Books You May Enjoy
7
Index
Appendix A: The Pegasus Bike Trainer

What’s agile all about?

Agile methods are – first and foremost – a means for improving the quality of your engineering work products. This is achieved through the application of a number of practices meant to continuously identify quality issues and immediately address them. Secondarily, agile is about improving engineering efficiency and reducing rework. Let’s talk about some basic concepts of agility.

Incremental development

This is a key aspect of agile development. Take a big problem and develop it as a series of small increments, each of which is verified to be correct (even if incomplete).

Continuous verification

The best way to have high-quality work products is to continuously develop and verify their quality. In other books, such as Real-Time Agility or the aforementioned Agile Systems Engineering books, I talk about how verification takes place in three timeframes:

  • Nanocycle: 30 minutes to 1 day
  • Microcycle: 1–4 weeks
  • Macrocycle: Project length

Further, this verification is best done via the execution and testing of computable models. We will see in later chapters how this can be accomplished.

Continuous integration

Few non-trivial systems are created by a single person. Integration is the task of putting together work products from different engineers into a coherent whole and demonstrating that, as a unit, it achieves its desired purpose. This integration is often done daily, but some teams increment this truly continuously, absorbing work as engineers complete it and instantly verifying that it works in tandem with the other bits.

Avoid big design up front

The concept of incremental development means that one thing that we don’t do is develop big work products over long periods of time and only then try to demonstrate their correctness. Instead, we develop and verify the design work we need right now, and defer design work that we won’t need until later. This simplifies the verification work and also means much less rework later in a project.

Working with stakeholders

A key focus of the Agilista is the needs of the stakeholders. The Agilista understands that there is an “air gap” between what the requirements say and what the stakeholder actually needs. By working with the stakeholder, and frequently offering them versions of the running system to try, they are more likely to actually meet their needs. Additionally, user stories – a way to organize requirements into short usage stakeholder-system usage scenarios – are a way to work with the stakeholder to understand what they actually need.