The CSD Requirements Ledger

One living source of truth for the whole design

The Requirements Ledger is the web tool that administers the 12-Step Collective System Design™ process. Every requirement a team discovers — functional requirements, design parameters, performance specs, and constraints — is captured in one ledger, traced back to the step where it was found, and checked against the question “how do you know, and with what certainty?” A real-time AI design coach reviews each entry as students work, without ever doing the design for them.

Proceed to the Log In Page → Watch the tour

Guided Tour

See the ledger in action

A short walkthrough of how a senior-design team captures requirements, builds the three CSD diagrams, and works alongside the AI coach — all in one tool that replaces a tangle of disconnected charts and documents.

How it fits together

The 12-Step Collective System Design Process

Collective System Design™ is taught as a disciplined, 12-step engineering design process — from problem statement and stakeholder needs, through functional requirements and design decomposition, to verification, validation, and standard work. Two companion resources support it:

The Primer teaches it

The 12-Step Design Process Primer is the interactive slide deck that explains each step — the concepts, the worked examples, and the reasoning behind them. It is how students and teams learn the method, and it grounds the AI coach’s answers.

The Ledger administers it

The Requirements Ledger is where teams do the work: filling in a template for each of the 12 steps, recording every requirement as a traceable row, mapping how the solution satisfies each one, and assembling it all into an editable technical report.

Go to the CSD Primer →

Why one ledger

CSD sees a system from many viewpoints

A real design is never described by a single diagram. Collective System Design™ deliberately draws on many established engineering viewpoints — the Flame Model, Axiomatic Design, FMEA, Verification & Validation, the Toyota Production System, Use Cases, INCOSE systems engineering, Process Capability (Cpk), and Design for X — all resting on the ISO/IEC/IEEE 42010 standard for multi-viewpoint architecture description.

Each viewpoint surfaces different requirements. Without a shared home, those requirements scatter across charts, spreadsheets, and slide decks and quietly fall out of sync. The Requirements Ledger is that shared home: every viewpoint feeds the same traceable ledger, so the design stays consistent as it grows.

One row per requirement — traced to the step that discovered it
Every requirement linked to how the solution achieves it
“How do you know?” and a certainty level on every claim
Diagrams, tables, and narrative generated from the same single source

The building blocks of Collective System Design: the 12-Step Methodology draws on the Flame Model, Axiomatic Design, FMEA, Verification and Validation, the Toyota Production System, Use Cases, INCOSE systems engineering, Process Capability (Cpk), and Design for X, on a foundation of ISO/IEC/IEEE 42010 multi-viewpoint architecture description. — The building blocks of CSD — many engineering viewpoints on a single ISO/IEC/IEEE 42010 multi-viewpoint foundation.

In the tool

What the Requirements Ledger owns

The Requirements Ledger

FRs, FRm’s, performance specs, and constraints in one place — the single source of truth, with full traceability back to the 12 steps.

The three CSD diagrams

System Boundary, Use Case Flow, and Design Decomposition — structured builders that replace Lucid and stay tied to the ledger.

A real-time AI coach

Reviews entries as you go — good FR, weak FR, “you may be missing…” — and talks through the process. It never authors your rows or finishes the project for you.

The technical report

Tables, diagrams, and ledger roll up automatically into a report draft that students edit to add the narrative of what they built.