Refining the CAD Prototype

Overview

This is lesson 8 of 18 in Design, Model and Make. Students use peer feedback to refine an Autodesk Inventor model, checking dimensions, joins, proportions and functionality before producing an updated version and recording a concise change log.

Learning intentions

Students will:

• interpret peer feedback and identify priorities for refinement
• check a CAD model against dimensions, joins, proportions and intended function
• apply suitable Inventor tools and processes to modify a prototype
• communicate design decisions using accurate technical language

Success criteria

• I can identify at least two specific improvements needed in my CAD prototype.
• I can modify dimensions, joins, proportions or features accurately in Inventor.
• I can test whether my updated model is functional and meets the design criteria.
• I can explain my changes and justify one design decision in a change log.

Curriculum links

• Analysing needs and opportunities, and selecting appropriate materials, systems, components, tools and equipment for designed solutions.
• Generating, testing, iterating and communicating design ideas and solutions using digital tools.
• Analysing how characteristics and properties of components and tools combine to create designed solutions.
• Developing design criteria, including sustainability, to evaluate design ideas and processes.
• Selecting and using suitable technologies and processes safely to make designed solutions.

Lesson structure (60 minutes)

1. 0–5 min · Hook and learning intention. Teacher displays a before-and-after CAD comparison in the introduction and comparison slides and asks, “How can a small change make a prototype more usable?” Students identify one visible improvement and review the learning intention and success criteria.

2. 5–12 min · Model the refinement process. Teacher demonstrates opening a previous Inventor file, checking a key measurement, editing a sketch constraint or feature, inspecting a join, and recording the change rather than simply overwriting the design. Students annotate the CAD refinement and change-log worksheet with the checks they must complete.

3. 12–20 min · Peer feedback review. Teacher explains respectful, evidence-based critique using the criteria: dimensions, joins, proportions, functionality and overall design intent. Students exchange their digital model or approved screenshots with a partner and complete the prototype testing feedback template, recording criterion-based evidence and a prioritised action.

4. 20–43 min · CAD refinement practical. Teacher conferences with pairs, checks that students save a new version, and reinforces safe workstation practice and responsible use of shared equipment. Students apply at least two justified changes in Inventor, checking constraints, alignment, clearances, joins and proportions as they work; they save the revised file using the agreed naming convention and update the CAD refinement and change-log worksheet.

5. 43–52 min · Function and quality check. Teacher pauses the class for a guided inspection using the testing and quality-check slides, prompting students to compare the revised model with the original and their design criteria. Students test the model through Inventor inspection tools, section or measurement views, and a visual functionality check, then make one final adjustment if evidence shows it is needed.

6. 52–60 min · Change log and exit reflection. Teacher displays the final prompts in the plenary slides and collects digital files or checks submission folders. Students complete the change log on the CAD refinement and change-log worksheet with the original issue, change made, evidence of improvement and next step, then answer: “Which change most improved the prototype, and how do you know?”

Resources

• Computers capable of running Autodesk Inventor
• Student Inventor files and agreed version-naming convention
• Projector or interactive display
• the CAD refinement and testing slide deck
• the CAD refinement and change-log worksheet
• the prototype testing feedback template
• Headphones if tutorial audio is used
• Design criteria from earlier lessons
• Workstation safety expectations

Assessment

• During peer review, check whether students give specific feedback linked to dimensions, joins, proportions and functionality rather than personal preference.
• Confer with students during modelling: ask them to justify each priority, identify the Inventor tool used, and explain how they will test the change.
• Collect the updated CAD file and change log. Use the exit response to assess whether students can connect a design decision to evidence of improved performance.

Differentiation

• Provide a visual checklist of the four required checks, a model change-log entry and sentence starters such as “The issue was…”, “I changed…”, and “This improved the prototype because…”.
• Allow students needing support to work from screenshots, receive a teacher-selected priority change, or complete one change with guided prompting before attempting a second.
• Pair students strategically for feedback, while ensuring each student makes and records changes to their own model.
• Extend confident students by asking them to compare two possible refinements, consider material use or printability, and justify the option that best balances function, appearance, efficiency and sustainability.
• Reinforce Respect, Integrity and Excellence through constructive critique, accurate file management, honest recording of changes and careful checking before submission.