Engineering concept
Before manufacturing, check launcher clearance, actual assembly geometry, fin symmetry, removable interfaces, support-free orientation and predicted filament mass.
IED Unit 3 • Lesson 3.8
Digital Assembly Design Review
Focus question: What evidence is needed before a multi-part rocket assembly is ready to manufacture?
Your lesson guide
Objective
Use Measure, Interference, and Section Analysis on critical rocket interfaces. Verify fin symmetry and assembly alignment. Review printed mass and wall thickness for material efficiency.
Materials
For the online work: a browser and your engineering notebook. Follow the activity’s materials list for any physical build, and get teacher approval before using equipment.
Plan your time
Suggested work block: 45–60 minutes. Physical builds and projects may span several classes; follow your teacher’s schedule.
IED Unit 3 • Lesson 3.8 • Learning Studio
Learn the concepts before completing the assignment
Today's engineering work
Measure the launch interface; inspect both couplers; confirm fin spacing at 120° or 90°; check walls, collisions and support-free print orientations; record PASS/FIX/UNVERIFIED.
Worked example
Example: 33 + 39 + 20 = 92 g predicted printed mass, within the 100 g printed-material planning threshold. This does not prove finished rocket weight.
01 / Illustrated concept
Digital Rocket Design Review
What the diagram means: Before manufacturing, check launcher clearance, actual assembly geometry, fin symmetry, removable interfaces, support-free orientation and predicted filament mass. The example values illustrate the principle and do not replace actual teacher-assigned dimensions.
02 / Watch and research
Instructional video and technical resources
Fusion assembly inspection
Use the relevant modeling or assembly technique; the demonstration project may differ from the rocket assignment.
Watch directly on YouTube ↗Expert references
Use these official Autodesk or NASA guides when the video alone does not explain the underlying workflow.
Primary technical reference ↗Additional learning resource ↗Self-study: identify a key technique, pause the tutorial, apply the operation and verify the result before continuing.
03 / Step-by-step guide
From theory to your own project
Guided task sequence
- Measure the launch interface
- inspect both couplers
- confirm fin spacing at 120° or 90°
- check walls, collisions and support-free print orientations
- record PASS/FIX/UNVERIFIED.
Worked example and verification
Example: 33 + 39 + 20 = 92 g predicted printed mass, within the 100 g printed-material planning threshold. This does not prove finished rocket weight.
Important: Do not substitute illustrative numbers for actual CAD dimensions, real measurements or instructor approvals.
04 / Independent practice
Explore one key parameter
Interactive concept explorer
Illustrative values only; not a completed engineering inspection or teacher authorization.
Check your reasoning
Does predicted filament mass equal finished rocket mass?
No. Fin material, hardware and real production affect final assembled mass.
What if a criterion has not been checked?
Mark NOT VERIFIED, not PASS.
Use the lesson's original assignment and “What to Submit” sections below for exact deliverable requirements.
Lesson Overview
What You Are Learning
Learning Targets
- Use Measure, Interference, and Section Analysis on critical rocket interfaces.
- Verify fin symmetry and assembly alignment.
- Review printed mass and wall thickness for material efficiency.
- Confirm disassembly and launcher compatibility before fabrication.
Unit 3 Progression
This is the formal gate between digital design and manufacturing.
ComponentsAssembleVerifyFabricateReviseFlight Test
Compressed-Air Rocket Challenge
Project Requirements
These requirements apply throughout Lessons 3.6–3.14.
1/2 in PVC Reference Tube
- The launcher tube outside diameter is 0.840 in (21.34 mm).
- Model the launch tube as a separate grounded Fusion reference component.
- You choose the rocket's internal launch clearance, but the finished rocket must slide freely over the actual PVC tube without binding.
- Before choosing the rocket's internal bore dimension, measure the actual unpressurized classroom launch tube. The 0.840 in (21.34 mm) diameter is the nominal outside-diameter reference, not the target bore size.
- The launcher itself is teacher equipment and is not modified as part of this project.
Modular 3D-Printed Rocket
- The structural rocket body is 3D printed in classroom-approved filament.
- Use at least 3 major printed modules: a lower launch/fin module, a main body module, and a nose/upper module.
- The rocket must have at least 2 removable printed-to-printed interfaces.
- Major printed modules must be disassembled without damaging the parts; permanent adhesive is not allowed between major modules.
Connection Method
- You choose how major modules connect.
- Examples include keyed/slip couplers with retention, twist-lock/bayonet features, screws/inserts, snap-fit features, or another approved method.
- The connection must keep the rocket aligned and secure during handling and flight-readiness checks.
- If a connection uses hardware or a tool, it must still be serviceable without damaging the printed parts.
Laser-Cut Fin Assembly
- Use 3 or 4 identical fins, equally spaced at 120° or 90°.
- Fins are laser-cut from 1/8 in acrylic or plywood.
- Use 3.175 mm as the nominal CAD thickness, then measure the actual stock and use that measurement for the final fin interface.
- Fins must use a repeatable locating feature such as slots, tabs, keyed pockets, or another approved feature. Surface gluing alone is not an acceptable locating method.
- Adhesive may be used to retain the fins after the fit/alignment check is approved.
Lightweight by Design
- Primary body walls should generally be 1.2–2.0 mm thick; 1.6 mm is the recommended target.
- Geometry thicker than 2.5 mm should be limited to local interfaces, couplers, fin mounts, fastener features, or other justified reinforcement.
- Total predicted 3D-printed material should be 100 g or less.
- The finished rocket should have a total mass of 125 g or less before the flight-readiness review.
Build for the Classroom Process
- Every printed component must fit the classroom printer build volume and be designed to print without support material.
- No support material may be required inside the launch bore or any mating interface.
- The nose must be rounded/blunt, and exposed fin corners/edges must be made safe before flight.
- Only the instructor operates, pressurizes, or changes settings on the compressed-air launcher.
Assignment
Complete the Pre-Manufacturing Design Review
Treat the rocket as an assembly system. A good-looking model does not pass until its interfaces and manufacturing constraints are verified.
Step-by-Step Instructions
- Verify the launcher interface: Use Measure and a section view to inspect the rocket around the 21.34 mm OD launcher reference. The rocket must have intentional clearance rather than an exact zero-clearance CAD match.
- Run interference analysis: Check the printed modules, fins, and launcher reference for unintended overlap.
- Verify fin symmetry: Confirm 3 fins are exactly 120° apart or 4 fins are exactly 90° apart.
- Inspect removable interfaces: Use Section Analysis to verify couplers, locks, fasteners, or snap features are physically assemblable and not trapped.
- Check wall thickness: Confirm primary shell walls are generally 1.2–2.0 mm and identify any local region over 2.5 mm that has a clear structural purpose.
- Check support-free manufacturing: Determine the print orientation for each printed part and confirm no support is needed.
- Check material estimate: Use the available Fusion/slicer estimate to confirm predicted printed material is 100 g or less.
- Check safe geometry: Confirm the nose is rounded/blunt and no fin geometry intentionally creates needle-like points.
- Resolve problems: Fix any failed item and repeat the affected check.
- Record the final review: Capture evidence showing the design is ready for manufacturing.
Before You Submit
- Launcher fit is intentional and measurable.
- No unexplained interference remains.
- Fin symmetry is verified.
- Both removable printed interfaces can assemble and disassemble.
- Printed material estimate is within the project limit.
- All parts have a support-free manufacturing orientation.
Submission
What to Submit
Submit only the following assignment-specific deliverables in Google Classroom:
Resources
Lesson Resources
IED Unit 3
Return to the Unit 3 lesson map and project sequence.
Introduction to Engineering Design
Return to the IED course hub.
Build your lesson report
Checkpoint: is your evidence ready?
- Check calculations, units, labels, and measurements against the activity requirements.
- Record what actually happened, including unexpected results.
- Explain what you changed and why; attach required drawings, photos, CAD, or code in your classroom assignment.
Submit only the following assignment-specific deliverables in Google Classroom: Design review report (one PDF): LastName_FirstName_3_8_DesignReview.pdf containing (1) measured launcher clearance and section view, (2) interference-check evidence, (3) fin spacing measurement, (4) two detachable-interface checks, and (5) predicted print mass plus planned print orientations. Pass/fix checklist (same PDF): mark each requirement PASS, NEEDS FIX, or NOT YET VERIFIED and write the specific correction for every failed item.
A PDF download is not a submission. Review it, then upload it and any required attachments through your classroom assignment system.