Introduction
Functional decomposition is a method of breaking down a system into individual components and studying their functions from a hierarchical perspective. It sets out to identify the major components or sub-systems and then evaluates each in detail. This paper will discuss the need for functional decomposition in systems engineering and the primary steps involved in the process. It will also provide practical examples of functional decomposition in action.
The Need for Functional Decomposition
Functional decomposition is essential in systems engineering, especially when the system is complex. It helps the engineer to decompose a system into small, manageable parts and analyse them individually, which aids in understanding the system as a whole. By breaking the system down into small, manageable parts, the engineer is better able to identify which parts are most important and which is not. It also helps identify suitable components for development as well as how to integrate and test the system as a whole.
The Primary Steps in Functional Decomposition
Functional decomposition is usually a multi-level process that involves several stages such as:
– Develop the hierarchical tree: This involves identifying the system objectives, the major components and sub-components and the ways these components interact with one another.
– Describe the component functions: This involves understanding the individual components and their functional requirements.
– Define how components interact: This involves defining the interaction between the components, including any necessary communication, as well as the physical layout of the components.
– Define interface requirements: This is the process of specifying the interface requirements between the components and other systems and/or external users.
– Allocate resources: This involves allocating resources to the development of the components and their interactions, as well as to the testing and maintenance of the overall system.
Practical Examples
One practical example of functional decomposition is the development of a mobile phone. The functional decomposition process would involve identifying the major components of a modern smartphone, such as the processor, display, camera, memory, battery and so forth. The engineer would then proceed to break these down into smaller components, for example the processor could be further broken down into discrete components such as the ARM9 and the various memory components.
Another example can be seen in the development of an automotive powertrain. This would involve breaking down the powertrain into its components, such as the engine, transmission, driveshaft, suspension, brakes, etc. Each of these components could then be further broken down into the various subsystems, such as the individual parts in the engine or the braking system.
Conclusion
Functional decomposition is a key process in systems engineering that involves breaking down a system into its individual components and studying their functions from a hierarchical perspective. It is essential in complex systems and helps to identify which components are most important and aids in developing and accurately testing the system as a whole. This paper has discussed the need for functional decomposition and the primary steps involved in the process, as well as providing practical examples of functional decomposition in action.
