Towing target
Tow a minimum load of 1 kg with the prototype.
Year 9 Engineering
The Mechanical Vehicle Project, explained.
A plain-English guide to what each folio section means, what evidence belongs there and what to do when you are not sure what comes next.
This is an independent assessment-support guide.
Complete the actual work in the template supplied by your teacher. Your current task sheet and classroom instructions always take priority.
Speed target
Travel at least 0.5 m/s when not towing.
Folio length
Up to 6–7 A3 pages, excluding title, contents and references.
What you submit
A design-process folio and a working vehicle prototype.
How to use this page
Assessment support without replacing the task
This page translates the project into simpler language and gives extra explanation when a folio section feels unclear.
Read the explanation
Open the folio module that matches the section you are currently completing.
Return to your class materials
Use the current task sheet and teacher-provided template for exact wording, dates and submission instructions.
Use the prompts to improve
Check whether your page includes evidence, justification and links to the engineering problem.
Ask when something conflicts
Your teacher's current instruction is the authority if it differs from anything written here.
Project pathway
The four stages of the assignment
Your teacher may set checkpoints within these stages. Check your current class schedule for the exact dates.
Explore
Understand the problem, investigate relevant products, study materials and identify the engineering knowledge needed.
Develop
Set the design direction, establish justified success criteria and improve ideas using evidence.
Generate
Communicate the final design, manufacture the prototype and collect reliable testing evidence.
Evaluate and present
Judge the solution against the criteria, recommend improvements and present the final outcome clearly.
The whole assignment
What are you actually designing?
01
A real vehicle concept
Your design decisions should make sense for a full-sized Australian vehicle that can tow, travel at an appropriate speed and still look appealing.
02
A testable prototype
The supplied vehicle kit, CAD software and available manufacturing tools are used to test important features of that larger concept.
03
A visible design process
The folio must show how research, calculations, testing and evaluation changed the design—not only display the final car.
Folio guide
Open the section you are working on
Each module explains the purpose, what belongs on the page and how to tell when you have enough evidence.
01 Exploring the problem — page 1Problem, knowns, assumptions, conditions and engineering concepts
What this section is for
Show that you understand the problem before jumping into a solution.
Include
- The problem rewritten clearly in your own words.
- Known information: performance targets, supplied kit, tools and prototype limits.
- Reasonable assumptions about the road, load, power supply or testing setup.
- Environmental and operating conditions relevant to an Australian towing vehicle.
- Engineering concepts and calculations that could affect the design.
You are ready to move on when…
- Every fact or assumption has a reason for being there.
- You have connected concepts such as torque, speed, gearing, friction and mass to the project.
- You have recorded useful dimensions or kit information before designing around them.
Avoid: copying the task sheet or listing random theory with no link to the vehicle.
02 Exploring the problem — page 2Drive layout, gears, materials, trailer and deeper research
Investigate the decisions that will shape the car
- Compare front-wheel drive and rear-wheel drive for towing and weight distribution.
- Study the available gear reductions and explain the speed–torque trade-off.
- Identify the material properties required for different vehicle parts.
- Study the trailer, its mass, wheel position and connection point.
- Extract useful information from the car assembly and gearbox booklets.
Strong analysis sounds like
“A double reduction may be more suitable because it increases wheel torque while still giving a theoretical speed above the required 0.5 m/s.”
That is stronger than: “I chose double reduction because it is best.”
03 Existing product researchFour relevant vehicles analysed using PMI
Choose around four useful products
Compare vehicles that teach you something about towing, form, material use, mass, layout or how function and aesthetics are balanced.
- Plus: What solves your problem well?
- Minus: What does not suit your problem?
- Interesting: What idea could you adapt or improve?
Stay relevant
Discuss towing capacity, body form, weight, useful materials, drivetrain or tow connection.
Do not fill the page with: touch screens, leather seats or ambient lights unless they genuinely affect this engineering problem.
04 Materials chart and analysisResearch properties, compare options and justify likely uses
Build the evidence first
For the materials comparison, include useful evidence such as cost, tensile strength, melting point, thermal conductivity, common uses, sustainability, corrosion resistance and sources.
- Use reliable sources and record them as you work.
- Compare materials for different parts rather than choosing one material for the whole car.
- Add an Ashby chart when it helps compare strength, mass, cost or another useful property.
The analysis matters more than the table
Explain which properties matter, which materials appear suitable, where each might be used and what trade-offs remain.
Example: steel may suit the main structure while aluminium reduces mass in selected components.
05 Design brief, success criteria and project planSet a clear design direction and define success
Design brief
Briefly explain the problem you have explored and state the direction your solution will take.
Success criteria
- Write five criteria that are specific enough to evaluate later.
- Include performance, aesthetics, material or sustainability considerations.
- Justify why each criterion matters.
Project plan
Highlight when each task should happen. Return at the end to explain what changed and why.
Make criteria measurable
Weak: “The car should be fast.”
Stronger: “Without a towing load, the prototype must travel at least 0.5 m/s over the set test distance.”
06 Initial ideasGenerate, iterate and evaluate using SLI
Show development, not one finished idea
- Use Fusion 360, sketches or both.
- Present an idea, change it, then explain what changed and why.
- Evaluate each meaningful stage using strengths, limitations and implications.
- Refer directly to the success criteria.
A useful annotation
Explains a decision and its effect: “The body was hollowed to reduce material and create room for the gearbox, but extra ribs are needed around the axle openings.”
A label alone is not analysis.
07 Refinement of ideaFix limitations and communicate the chosen concept in detail
Take the best idea forward
- Improve the limitations identified during initial ideas.
- Show body form, gear selection, component placement and the tow connection.
- Include circuit considerations and cable access where relevant.
- Use close-ups and multiple views to communicate detail.
- Use physical tests, trial prints or FEA when they genuinely help.
The emphasis changes here
There should be fewer completely new ideas and more evidence that the selected idea is becoming workable, manufacturable and stronger against the criteria.
08 Final ideaCommunicate the resolved design and justify it
Include
- A clear CAD model or high-quality render.
- Useful views, including the tow connection and internal layout where needed.
- An orthographic drawing with full-size dimensions.
- Annotations that justify how the design satisfies each criterion.
- Materials, gearing and manufacturing decisions.
Remember the two scales
The page communicates the intended real vehicle design. The kit-based prototype tests selected attributes of that design.
09 Prototype and testingPhotographs, procedures, results, calculations and analysis
Test the two required performances
- No-load speed: complete repeated trials over a measured distance.
- Towing: test the vehicle with the required 1 kg load and record what happens.
- Photograph the prototype and testing setup.
- Present results in a table with units.
- Calculate averages and compare actual results with predictions.
Analysis answers “why?”
Explain patterns, unexpected results, wheel slip, axle bending, mass, traction, gearing or other design features that affected performance.
One result is not enough. Repeated trials make the conclusion more reliable.
10 EvaluationJudge success using criteria and evidence
Evaluate each criterion separately
- State whether the design met, partly met or did not meet the criterion.
- Use test data, calculations, CAD evidence or observations.
- Discuss the intended real vehicle as well as the prototype.
- Explain environmental impacts of likely materials.
- Recommend realistic future improvements.
Use evidence, not opinions
Weak: “The car worked well.”
Stronger: “The prototype averaged 0.62 m/s without a load, exceeding the 0.5 m/s criterion by 0.12 m/s.”
11 Presentation of solution and bibliographyOne-page communication and complete referencing
Presentation poster
- Fit the presentation on one slide.
- Include the problem, a prototype photograph with trailer, CAD renders and concise justification.
- Design it as though this were the only page a viewer would see.
Bibliography
Use APA referencing and acknowledge every source used for research, images, data or calculations.
Final check
Can a reader understand the problem, the final solution, why it was chosen and how well it performed without reading every earlier page?
Calculation toolbox
Useful relationships for this project
Use only the formulas that help answer a design or testing question. Always show formula, substitution, answer, unit and what the result means.
Measured performance
Speed
distancetime
Use for the actual prototype test. Measure the same distance each trial.
Gearbox
Gear ratio
driven gear teethdriver gear teeth
A larger reduction normally increases available wheel torque but reduces output speed.
Gearbox
Output speed
input rpmgear ratio
Use to compare theoretical output speeds for the available reductions.
Wheel motion
Wheel circumference
C = πd
Use the wheel diameter in metres when calculating linear speed in m/s.
Theoretical speed
Wheel linear speed
wheel rpm × circumference60
Compare the prediction with the measured prototype speed and explain any difference.
Towing
Rolling resistance
Fr = Crrmg
Use a defensible rolling-resistance coefficient and clearly explain the assumptions.
Wheel force
Force at the wheel
wheel torquewheel radius
Useful when checking whether the wheel force should overcome the estimated resistance.
Optional comparison
Performance index
mass supportedmass of solution
Use only when it adds a meaningful comparison and explain what a larger value represents.
What strong work looks like
The evidence chain
Find information that matters to the design.
Use that evidence to choose a direction.
Show how the idea changed in CAD or testing.
Collect repeatable performance evidence.
Judge the final solution against the original criteria.
Strong work makes this chain visible from beginning to end.
Calculations, material comparisons, repeated CAD development, testing data and criterion-by-criterion evaluation should all connect back to the original engineering problem.
Important
Use your current class instructions
This independently created support page does not host or replace school assessment documents. Check the materials provided by your teacher for current dates, required file formats, checkpoints and submission instructions.