Session 9: “Printing and Testing Bridges”
Architect:
Syed Shayaan Haider - Markhor3D
Session Overview
In this session, Grade 5 students will see their bridge designs come to life as they are 3D printed. Working in groups, students will assemble their printed bridge pieces and then test the strength of their bridges by gradually adding weight until failure occurs. They will record the maximum weight each bridge held and analyze which design elements contributed to better performance. Emphasis is placed on safety during testing and careful observation of the results.
Learning Objectives
By the end of the session, Grade 5 students will:
- Assemble Printed Bridges: Put together the various printed parts of their bridge designs.
- Test Structural Strength: Gradually add weight to their bridges to determine how much load they can support.
- Record and Analyze Results: Document the maximum weight held and identify which design features (such as trusses, ribs, fillets, or chamfers) improved strength.
- Follow Safety Precautions: Understand and adhere to safety guidelines during the testing process.
Teaching Aids
Visual Aids:
- Demonstration Videos: Short clips showing safe weight testing procedures.
- Step-by-Step Guides: Slides illustrating the process of assembling bridge components and adding weight gradually.
- Example Data Sheets: Templates for recording weight limits and observations.
- Infographics: Visual guides on safety precautions and testing methods.
Required Equipment:
- 3D Printer:
- The bridge models should be printed and available for assembly.
- Printed Bridge Components:
- Each group’s assembled bridge design.
- Weight Testing Materials:
- Small weights (e.g., coins, washers, or standardized weights) or a way to add incremental weight safely.
- Measuring Tools:
- Rulers or digital scales (if available) to help record weight.
- Notebooks and Pens:
- For students to record their testing results and observations.
- Safety Equipment:
- Safety goggles and any necessary barriers to ensure safe testing.
- Interactive Whiteboard/Projector:
- For demonstrating testing procedures and showing example data.
Structure and Lesson Plan (Total Time: 60 minutes)
1. Introduction and Linking to Previous Sessions (10 minutes)
- Greet the Students:
- “Good morning, everyone! Today, we’re going to see our bridge designs become real and test how strong they are.”
- Recap Previous Sessions:
- “Previously, you designed your bridges using principles of structural strength, efficient material use, and precise measurements. Today, we’ll assemble those bridges and put them to the test.”
- Explain the Session Overview:
- “We will first assemble your printed bridge pieces and then test their strength by adding weight gradually until they fail. Make sure to follow all safety precautions during testing.”
2. Assembling the Bridges (15 minutes)
- Explain Assembly Steps:
- “Work with your group to carefully assemble your bridge. Make sure that all parts align correctly and that the structure is stable.”
- Hands-On Activity:
- Each group assembles their printed bridge pieces.
- Use alignment techniques to ensure proper fit between parts.
- Verify that the final assembled bridge meets the design dimensions (25 cm long, 6 cm deep, 6 cm high).
- Teacher Support:
- Circulate to assist groups with assembly and ensure proper connections between parts.
3. Testing the Bridges (20 minutes)
- Explain the Testing Procedure:
- “Once your bridge is assembled, we will test its strength by gradually adding weight. We will add weight slowly until the bridge fails, and you will record the maximum weight it held.”
- Demonstrate Safe Testing:
- Show a short demonstration video or live demo of how to add weights safely.
- Emphasize safety: “Always add weight gradually and make sure no one is standing close to the bridge during testing. Wear safety goggles if needed.”
- Hands-On Testing Activity:
- Each group adds weight incrementally to their bridge.
- Students record the maximum weight supported before failure using a provided data sheet.
- Discuss observations such as where the bridge started to bend or break.
- Teacher Support:
- Monitor the testing process to ensure safety.
- Assist with recording data and troubleshooting if a bridge fails unexpectedly.
4. Recording and Initial Analysis (10 minutes)
- Group Discussion:
- “Discuss within your group what parts of your bridge held up well and which parts failed first.”
- Record Data:
- Use data sheets to record the maximum weight supported by each bridge.
- Note any visible design issues such as weak joints, excessive bending, or stress concentration.
- Teacher Support:
- Ask guiding questions like, “Did the trusses help make the bridge stronger?” or “How did the use of fillets or chamfers affect the strength?”
5. Conclusion and Preview of Next Session (5 minutes)
- Summarize the Session:
- “Today, you assembled and tested your bridge designs. You recorded how much weight each bridge held and began to understand which design elements contribute to strength.”
- Preview Next Session:
- “In our next session, we will reflect on these results and learn how to optimize our designs further. We’ll discuss ways to improve strength while minimizing material use.”
- Closing Encouragement:
- “Great work today, everyone! Your observations and data will help you make even stronger designs next time.”
For suggestions, improvements, and corrections, feel free to reach out at shayaanhaider@gmail.com