Complexity Growth in Aerospace Systems

Use of self-learning and resilient components permits aerospace systems today to achieve more and accomplish tasks that were otherwise not possible. This degree of freedom however has led to an almost exponential growth in system complexity the past few decades.

The figure measures the complexity growth using on-board lines of source code in thousands. Data compiled from [1] -[4].

New Challenges

Complexity in a system stems from Interaction! Whether it is:

Interaction between the various subsystems
Interaction between the environment and the subsystem(s)
Interaction between “agents”
or lot more

The result of this interaction is the proliferation of:

Near infinite state space/ environmental conditions, and
Composition of system(s) in a way that may result in potentially catastrophic behavior

Impact on Cost and Constraints on Innovation

The direct consequence of software complexity is emergent and sometimes even unexpected behavior due to interaction between different components of software and hardware. Further, testing, evaluating and certifying each of these consequences places unmanageable demands on computational resources and development cost.