The engineering idea
A revolute joint removes five of six rigid-body freedoms and leaves one rotation about a pivot axis.
IED Unit 3 • Lesson 3.1
Revolute Joints & Rotational Motion
Focus question: How can a joint allow one component to rotate while keeping the rest of an assembly constrained?
Your lesson guide
Objective
Apply previously learned rigid joints to stationary components. Create a revolute joint with a correctly located pivot axis. Ground the base and test the remaining degrees of freedom.
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.
Unit 3 Learning Studio • Lesson 3.1
Understand, visualize, and apply the concept
Apply it to this project
One base bracket + one moving arm + one pin + two spacers + one cap = six supplied parts. The arm should rotate; all fixed hardware should stay constrained.
What successful work shows
- Ground the fixed bracket first.
- Rigidly attach spacers, retainer and stationary hardware.
- Choose the pivot center and axis for the moving arm.
01 / Learning diagram
Revolute Joints & Rotational Motion — visual walkthrough
Interpret the illustration: A revolute joint removes five of six rigid-body freedoms and leaves one rotation about a pivot axis. Treat the diagram as an explanatory model, not as a dimensioned Fusion part or an approved fabrication file.
02 / Watch and learn
Video demonstration and technical references
Moving hinge joints in Fusion
Pause the video at relevant commands or principles and apply them to this lesson. The tutorial's sample design may differ from your teacher-supplied parts and rocket specifications.
Watch directly on YouTube ↗Read the expert explanations
Official Autodesk Fusion or NASA guidance provides further diagrams and step-by-step instruction.
Primary technical reference — help.autodesk.com ↗Additional worked reference — help.autodesk.com ↗Self-study routine: read the explanation, identify a concrete command or concept, do that step in your own file, and capture evidence before proceeding.
03 / Practical walkthrough
Follow the lesson workflow
Guided sequence from the assignment
- 1. Create a new Fusion design named
LastName_FirstName_3_1_Hingeand insert all six supplied parts as components. - 2. Ground the base bracket and rename every component clearly in the Browser.
- 3. Assemble stationary hardware with the rigid-joint skills learned in Unit 2.
- 4. Create a revolute joint about the correct pivot axis so the arm rotates relative to the grounded bracket.
- 5. Drag or Drive Joint to test rotation; correct any unwanted translation or detached parts.
- 6. Save the completed assembly and record a short demonstration with the base visible.
Worked example & mistakes to avoid
One base bracket + one moving arm + one pin + two spacers + one cap = six supplied parts. The arm should rotate; all fixed hardware should stay constrained.
Check your evidence: Choose the pivot center and axis for the moving arm. Verify with the actual CAD geometry, teacher-assigned parameters or physical observations—not just with the example shown here.
When stuck: return to the lesson's diagram, review the relevant section of the video, and compare your setup with the specific checklist in the assignment below.
04 / Interactive learning and review
Investigate and explain the key requirement
Concept explorer
Change a sample parameter, then explain what it means. These are illustrative values, not measured student results or approved settings.
Check your understanding
What is the single allowed motion?
Rotation around one defined axis.
What should not move?
The grounded bracket and all hardware that is rigidly attached to it.
Before you submit
Identify the actual Fusion file, screenshot, drawing, PDF, video or physical measurement requested below. Save original evidence, not simply a screenshot of this webpage.
Lesson Overview
What You Are Learning
Learning Targets
- Apply previously learned rigid joints to stationary components.
- Create a revolute joint with a correctly located pivot axis.
- Ground the base and test the remaining degrees of freedom.
- Demonstrate that the pivot arm rotates without coming loose.
Unit 3 Progression
You already made a Puzzle Cube assembly using rigid joints in Unit 2. This lesson introduces controlled motion—not another body-to-component exercise.
RevoluteSliderLimitsMechanismsVerifyRocket Design
Assignment
Hinged Bracket: Revolute Joint Challenge
Use the teacher-provided individual Fusion parts: 1 base bracket, 1 pivot arm, 1 pivot pin, 2 spacers, and 1 retaining cap. Do not remodel the parts.
Step-by-Step Instructions
- Create a new Fusion design named
LastName_FirstName_3_1_Hingeand insert all six supplied parts as components. - Ground the base bracket and rename every component clearly in the Browser.
- Assemble stationary hardware with the rigid-joint skills learned in Unit 2.
- Create a revolute joint about the correct pivot axis so the arm rotates relative to the grounded bracket.
- Drag or Drive Joint to test rotation; correct any unwanted translation or detached parts.
- Save the completed assembly and record a short demonstration with the base visible.
Before You Submit
- Exactly six supplied parts are present (including two spacers).
- The base remains fixed; the arm rotates about the correct pin axis.
- No component slides away or moves independently unless intentionally designed.
Submission
What to Submit
Upload the following specific items to the Lesson 3.1 assignment in Google Classroom:
Submission check: Submit the actual working assembly—not a screenshot of an unassembled parts kit.
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.
Upload the following specific items to the Lesson 3.1 assignment in Google Classroom: Fusion file (.f3d): export the completed hinge assembly as LastName_FirstName_3_1_Hinge.f3d. The base must be grounded and revolute/rigid joints saved. Motion recording (.mp4, 10–20 seconds): show the assembled hinge in Fusion, move the arm through its available rotation, and demonstrate that the grounded base does not move.
A PDF download is not a submission. Review it, then upload it and any required attachments through your classroom assignment system.