Task: Allocate Requirements to Engineering Disciplines
This task takes the requirements allocated to a subsystem as a whole and allocates them to the different engineering disciplines involved (e.g. software, electronics, mechanical, optical, hydraulic).
Disciplines: System Engineering Architecture
Purpose
The purpose is to clearly delineate the required contributions of different engineering disciplines to the engineering development of a subsystem by allocating the requirements allocated to the subsystem by the system engineering team.
Relationships
Main Description
A subsystem team is usually comprised of engineers within different disciplines, such as software, digital electronics, analog electronics, hydraulic, pneumatic, control, and mechanical. Once the subsystem specification is handed off, certain of the requirements will belong to one discipline or the other. Other requirements will require decomposition into derived requirements, allocating portions of a subsystem-level requirement to different discipline. This is particularly true of quality-of service requirements.
Steps
Review subsystem requirements
This step examines the subsystem specifications in all its forms - including SysML models, state and control specifications, requirements specifications, and logical and physical subsystem interfaces to make sure that the interdisciplinary team understands what is necessary. If requirements are missing, incomplete, inadequate, or incorrect, clarification from the system engineering team or subject matter experts must be sought.
Allocate single-discipline requirements
Many of the requirements will be clearly related to a single discipline. These may be allocated directly.
Decompose multi-discipline requirements
Many subsystem requirements require the interaction of one or more engineering disciplines. Clarity as to which responsibility will be met by which discipline is required. This is best done with a collaboration of the engineering staff from all relevant disciplines - such as electronics and software - to arrive at an optimal solution. This results in derived requirements. Derived requirements must together met the original subsystem requirement.
Allocate derived requirements
Each derived requirement should be allocated to a single subsystem engineering discipline. If a derived requirement cannot be allocated to a single subsystem, then it must be further refined.
Update traceability record
Depending on the level of traceability required, the traceability record for the requirements should be updated to show which engineering discipline within the subsystem has responsibility for meeting the allocated requirements.
Review allocations
This step constitutes a review of the requirements, their deviations, and their allocations with an eye towards coverage (all subsystem requirements must be allocated), completeness (identify any missing requirements), and achievability.