Lesson 43 · Unit 6
IA Day 13 —
Criterion D Launch
Plan the physical fidelity model and the multiple model–test–refine cycles that will turn your selected idea into the intended solution.
80 minutesIA Criterion D · B2.1.12–13
Physical model
Test plan
Iterate
Guiding question: What should your fidelity model prove before you spend time making it polished?01
Today’s destination
By the end of class, you should be able to…
01
Read Criterion D
Know what “develop a fidelity model” requires.
02
Plan the physical model
Choose fidelity based on the design questions.
03
Plan multiple cycles
Make testing and refinement visible over time.
04
Connect every test
Tie testing to specifications and intended-user needs.
Success check: Produce clear, criterion-aligned IA evidence during today’s studio block.
IA DAY 13 · Criterion D launch02
Design project requirement
You need a physical fidelity model for testing and evaluation.
Digital CAD, drawings and simulations can support the development process, but the guide explicitly requires a physical fidelity model as part of the design project.
Fidelity ≠ perfection. Fidelity means the model is accurate enough to test the intended design questions with the intended user.
IA requirement · physical fidelity model03
ModelCreate a representation at useful fidelity.
TestGather performance data + user evidence.
AnalyseCompare results to specifications.
RefineChange a design feature for a reason.
RepeatRun multiple cycles until major requirements are addressed.
B2.1.12 · multiple model-test-refine cycles04
Geometry
Foam/card/3D print can test size, reach, clearance or fit.
Interaction
A working mock-up can reveal grip, movement, confusion or errors.
Structure / performance
A physical model or suitable simulation can test load/deflection/strength assumptions.
Appearance / communication
CAD or higher-fidelity surfaces can support form, proportion and visual feedback.
Use a range of graphical, physical and/or digital modelling where it helps the development. The physical fidelity model remains required.
Select the model that answers the question05
| Specification | Design uncertainty | Model / test | Data to collect | User involved? | Decision rule |
|---|---|---|---|---|---|
| S1 | What might fail? | How will you test? | Measure / observe | Who? | What result triggers refinement? |
| S2 | What is unknown? | Appropriate fidelity | Evidence | How? | Pass / revise logic |
Plan evidence, not just construction06
Studio block
The mini-lesson is short. The evidence-making is the lesson.
60+minutes work
Freeze the selected direction
Bring Criterion C into a clear starting point for D.
Bring Criterion C into a clear starting point for D.
Create the test matrix
Map major specifications to a model/test and evidence type.
Map major specifications to a model/test and evidence type.
Plan the physical fidelity model
Materials, scale, functional features, tools, safety and user access.
Materials, scale, functional features, tools, safety and user access.
Start model v1
Build only as much fidelity as needed to answer the first questions.
Build only as much fidelity as needed to answer the first questions.
IA studio · planning + build07
Physical fidelity model planned
It can be tested with the intended user.
RequiredIt can be tested with the intended user.
Multiple cycles planned
There is room for evidence-based change.
DThere is room for evidence-based change.
Tests map to specifications
Every test has a reason.
DEvery test has a reason.
Evidence type is clear
You know what data / feedback to capture.
DYou know what data / feedback to capture.
Criterion D · plan before polish08
Exit ticket
Before you leave…
1. State what your physical fidelity model must physically demonstrate.
2. Name the first test and the specification it targets.
3. Identify what evidence will tell you to refine the design.
Next lesson
IA Day 14 — Fidelity Model Build & Test: Cycle 1
Keep the evidence chain moving: user → research → decision → test.
Curriculum alignment
IA Criterion D: develop and annotate iterative fidelity models through multiple testing and refinement cycles to arrive at the intended redesigned solution; test against design specifications and intended-user needs. The design project requires a physical fidelity model for testing and evaluation. B2.1.12–13: iterative model-test-refine and feasible models at appropriate fidelity generating performance data with end-users.
IA Criterion D: develop and annotate iterative fidelity models through multiple testing and refinement cycles to arrive at the intended redesigned solution; test against design specifications and intended-user needs. The design project requires a physical fidelity model for testing and evaluation. B2.1.12–13: iterative model-test-refine and feasible models at appropriate fidelity generating performance data with end-users.
Lesson complete9 slides
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IB Design Technology SL · Lesson 4309