I can create a free body diagram with the correct external forces, directions, and labels.
POE Unit 2 • Lesson 2.3
Free Body Diagrams
Focus question: How can a free body diagram isolate the forces that control a structure?
Mission Briefing
Today’s Plan
A focused sequence that builds toward the aerospace payload support structure challenge.
Opening promptConcept modelGuided analysisInteractive practiceEvidence checkExit ticket
Lesson Targets
What You Will Be Able to Do
Complete free body diagram
The diagram isolates one object and includes weight, support reactions, and any applied force without adding internal or imaginary forces.
Activity Flow
How the Lesson Moves
Each step builds the structural reasoning needed for the lesson deliverable.
1. Choose the body
Define exactly what object or assembly is isolated.
2. Replace the surroundings
Show contacts, supports, cables, and gravity as external forces.
3. Check completeness
Verify directions, labels, and a useful coordinate system.
Lesson Interactive
Build the Free Body Diagram
Select only the external forces that belong on the isolated payload platform.
Isolated Platform
The platform and payload are isolated together. The pin and cable are replaced by reaction forces.
Forces to Include
A free body diagram contains external forces and moments acting on the isolated body.
Today’s Work
Main Deliverable
Payload-Beam Free Body Diagram
Create one complete free body diagram for the assigned beam or support.
- Show every external force with a labeled arrow and coordinate axes.
- State the equilibrium or motion assumption used for the diagram.
Exit Ticket
Mission Debrief
State one structural idea from today in your own words.
Name one calculation, measurement, diagram, or observation that could support a design decision.
Identify one question or risk to carry into the next structural lesson.
Resources
Lesson Resources
Lesson 2.3 PowerPoint
Use the presentation to review the lesson concepts, examples, and activity directions.
Principles of Engineering
Return to the POE course hub for units, resources, certifications, and current course information.
Aerospace Payload Support Structure
Use this unit project context when connecting analysis, material decisions, prototype testing, and final design-review evidence.