BOM
Bill of materials structures, types, and processes.
Bill of Materials
BOMA structured list of every component, material, and part needed to manufacture a product.
BOM Explosion
The process of expanding a top-level assembly BOM into all its constituent parts and sub-assemblies.
Engineering BOM
eBOMThe BOM that captures design intent, maintained by engineering throughout development.
Indented BOM
A multi-level BOM that uses visual indentation to show parent-child relationships between assemblies and components.
Manufacturing BOM
mBOMThe production-oriented BOM that reflects how a product is actually assembled, including fixtures and consumables.
Requirements
Requirements engineering standards and artifacts.
Acceptance Criteria
The measurable conditions a system or component must meet to be considered complete and accepted.
Functional Requirements
Statements of what a system must do — behaviors, inputs, outputs, and capabilities.
IEEE 29148
The IEEE standard for requirements engineering, defining processes and criteria for well-formed requirements.
Non-Functional Requirements
NFRRequirements that define quality attributes — how well a system performs, rather than what it does.
Requirements Traceability Matrix
RTMA document that links requirements to their sources, design elements, and verification tests.
System Requirements Specification
SRSA formal document defining all requirements a system must satisfy, derived from stakeholder needs.
Design
Design methods, reviews, and decisions.
Concept Trade Study
A structured comparison of design alternatives against a set of requirements and evaluation criteria.
Design Decision Log
A structured record of key engineering decisions, capturing the objective, alternatives, analysis, and rationale.
Design for Assembly
DFADesigning products to minimize assembly time, steps, and the potential for assembly errors.
Design for Manufacturing
DFMAn engineering practice of designing products to be easy and inexpensive to manufacture at volume.
Design Freeze
A formal milestone after which no further design changes are permitted without a formal change order process.
Design Specification
A document that describes how a system will be designed to meet its requirements — the 'how' to the SRS's 'what.'
Interface Control Document
ICDA document that defines all interfaces between systems, subsystems, or components — signals, protocols, mechanical interfaces, and power.
Make-or-Buy Decision
The analysis of whether to manufacture a component in-house or purchase it from a supplier.
Testing
Verification, validation, and test phases.
Design Verification Test
DVTThe second prototype phase — verifying the design meets all specifications with production-representative builds.
Engineering Verification Test
EVTThe first hardware prototype phase — focused on verifying that the design concept works and meets core requirements.
Failure Mode and Effects Analysis
FMEAA systematic method for identifying potential failure modes, their causes, their effects, and their risk priority.
Hardware-in-the-Loop
HILA testing technique where real hardware is connected to a simulated environment to test control systems before physical prototypes are available.
Production Validation Test
PVTThe final pre-production phase — validating the manufacturing process can produce compliant product at volume.
Risk Priority Number
RPNA calculated score in FMEA (Severity × Occurrence × Detection) used to prioritize failure modes for corrective action.
Verification and Validation
V&VVerification confirms a design meets its specifications; validation confirms the product meets user needs.
Process
Engineering process, readiness, and governance.
Configuration Management
CMThe discipline of tracking and controlling changes to hardware, software, and documentation throughout a product's lifecycle.
Critical Design Review
CDRThe design gate before production build authorization — confirming the detailed design meets all requirements and is ready for manufacturing.
Design History File
DHFAn FDA-mandated compilation of all records that demonstrate a medical device was designed in compliance with its approved design plan.
Engineering Change Order
ECOA formal document that authorizes and records a change to a product's design, BOM, or specifications.
Hardware Readiness Level
HRLAn extension of TRL specifically for hardware, tracking manufacturing and production readiness alongside technology maturity.
Preliminary Design Review
PDRA design gate review that verifies the design approach is feasible and requirements are allocated before detailed design begins.
Technology Readiness Level
TRLA NASA-originated 1–9 scale measuring the maturity of a technology from basic research to operational deployment.
Work Breakdown Structure
WBSA hierarchical decomposition of a project into all the work required to deliver it — the foundation of project planning.
A–Z Index
A
The measurable conditions a system or component must meet to be considered complete and accepted.
B
A structured list of every component, material, and part needed to manufacture a product.
The process of expanding a top-level assembly BOM into all its constituent parts and sub-assemblies.
C
A structured comparison of design alternatives against a set of requirements and evaluation criteria.
The discipline of tracking and controlling changes to hardware, software, and documentation throughout a product's lifecycle.
The design gate before production build authorization — confirming the detailed design meets all requirements and is ready for manufacturing.
D
A structured record of key engineering decisions, capturing the objective, alternatives, analysis, and rationale.
Designing products to minimize assembly time, steps, and the potential for assembly errors.
An engineering practice of designing products to be easy and inexpensive to manufacture at volume.
A formal milestone after which no further design changes are permitted without a formal change order process.
An FDA-mandated compilation of all records that demonstrate a medical device was designed in compliance with its approved design plan.
A document that describes how a system will be designed to meet its requirements — the 'how' to the SRS's 'what.'
The second prototype phase — verifying the design meets all specifications with production-representative builds.
E
The BOM that captures design intent, maintained by engineering throughout development.
A formal document that authorizes and records a change to a product's design, BOM, or specifications.
The first hardware prototype phase — focused on verifying that the design concept works and meets core requirements.
F
A systematic method for identifying potential failure modes, their causes, their effects, and their risk priority.
Statements of what a system must do — behaviors, inputs, outputs, and capabilities.
H
An extension of TRL specifically for hardware, tracking manufacturing and production readiness alongside technology maturity.
A testing technique where real hardware is connected to a simulated environment to test control systems before physical prototypes are available.
I
The IEEE standard for requirements engineering, defining processes and criteria for well-formed requirements.
A multi-level BOM that uses visual indentation to show parent-child relationships between assemblies and components.
A document that defines all interfaces between systems, subsystems, or components — signals, protocols, mechanical interfaces, and power.
M
The analysis of whether to manufacture a component in-house or purchase it from a supplier.
The production-oriented BOM that reflects how a product is actually assembled, including fixtures and consumables.
N
Requirements that define quality attributes — how well a system performs, rather than what it does.
P
A design gate review that verifies the design approach is feasible and requirements are allocated before detailed design begins.
The final pre-production phase — validating the manufacturing process can produce compliant product at volume.
R
A document that links requirements to their sources, design elements, and verification tests.
A calculated score in FMEA (Severity × Occurrence × Detection) used to prioritize failure modes for corrective action.
S
A formal document defining all requirements a system must satisfy, derived from stakeholder needs.
T
A NASA-originated 1–9 scale measuring the maturity of a technology from basic research to operational deployment.
V
Verification confirms a design meets its specifications; validation confirms the product meets user needs.
W
A hierarchical decomposition of a project into all the work required to deliver it — the foundation of project planning.
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