System Life Cycle Thinking
System life cycle thinking adds another dimension to systems engineering. The system lifecycle is the fundamental roadmap for understanding and communicating how systems evolve through a progression of sequential life cycle phases. Understanding this life cycle is the foundation for system development. System life cycle thinking adds the ability to assess existing system capabilities and performance relative to threats and opportunities along with defining, procuring, developing and then implementing systems to achieve mission objectives that counter or leverage those threats and opportunities. One of the primary tools used in this process is the life cycle cost, which is the cost of planning, building, fielding, operating, and supporting a system or part thereof for the duration of its use. It is the cost to perform the following for a system- research and development, production, operations and support, disposal. Cost touches all the phases of a system, from procurement to production and operations, so being able to analyze cost for each of those phases and determine how to minimize life cycle cost while meeting user requirements is essential to system success and is a key part of system life cycle thinking. Some expected benefits from implementing this mode of thought would be greater efficiency, reduced costs, and a plan for the life of the system.
The product life cycle diagram above contains two main phases, the acquisition phase and the utilization phase, along with some associated interfaces and interactions for each. Some of these interactions are similar to that of the system life cycle. Both cycles begin with a concept (a preliminary design) where the system and product are defined in terms of how they will solve a problem. The entire product life cycle acquisition phase is similar to the system life cycle development phase as both cycles design and then verify their respective components. The production operations product life cycle interaction is similar to the production system life cycle phase as the activities performed deal with verifying the production and manufacturing processes, ensuring the component meets user requirements, and the entire component has been inspected, verified, and deployed successfully. The product life cycle includes a utilization phase in which support & maintenance and disposal are interactions. This is similar to the operations & support and disposal phases of the system life cycle. Once products and systems are launched, there are myriad activities that need to be done in order to operate, maintain, and support the component. This includes refinement and enhancement upgrades and capability adjustments. During the disposal phase activities are performed that phase out the component through sale, lease, disposal, burial, or disassembly. Once an engineer understands the system life cycle process, it is easier to understand other sub-processes, like the product life cycle, which is very similar to the system life cycle.
“Designing for the life cycle” is a phrase that is often used when referring to system life cycle thinking. The full meaning of it is that the system design needs to be created in such a way that it can be easily adaptable throughout the life cycle. For example, all systems will eventually be disassembled or integrated into another system, so when designing a system it is important to have an incremental deprecation plan in mind for how to efficiently dispose of this system in the future. The system is a living, breathing object, which needs to be able to adapt as time progresses. It should still be clearly defined in terms of its functionality, etc., however there needs to be built in ability for change so any change won’t destroy the system or render it useless.
