Work On
- Detailed concept sketches or a CAD model with a labeled mechanism plan
- Freestanding VEX cargo lift
- Guided payload platform
- Motor-powered lifting system
- Three official test trials
- At least one engineering revision
- Work and power calculations
POE Unit 1 • Final Project • Lesson 1.9
Unit 1 Final Project: VEX Cargo Lift Engineering Challenge
Challenge: Design and build a VEX cargo lift that raises a 500 g payload at least 400 mm vertically and completes three consecutive successful trials.
Start Here
What You Need to Do
Use this as your checklist throughout the challenge.
Submit
- Initial detailed concept sketches or CAD model
- Mechanical-system / gear-ratio explanation
- Three-trial test data
- Average lift time
- Work calculation
- Power calculation
- Problem observed + design revision
- Final reflection
Done When
Your lift raises the 500 g payload at least 400 mm, remains freestanding, keeps the payload guided, and completes three successful trials in a row.
Requirements
Your Lift Must Include
Structural Frame
A freestanding VEX structure that supports the lift and remains upright without being held.
Payload Platform
The payload must sit on a platform, tray, or carrier. It may not simply hang from the string.
Guided Vertical Motion
Use rails, channels, rollers, wheels, sliding guides, or another approved method so the platform moves primarily up and down.
Motor-Powered Lift
A VEX motor must provide the lifting power. No manual assistance is allowed during an official trial.
Power Transfer
Use a winch/drum, gears, chain and sprockets, pulleys, or an appropriate combination.
Stable Base
The lift must support itself throughout operation. Students may not stabilize it by hand.
Performance Standard
What Counts as Success?
| Requirement | Standard |
|---|---|
| Payload mass | 500 g |
| Vertical lift distance | 400 mm minimum |
| Successful trials | 3 consecutive trials |
| Power source | VEX motor |
| Student assistance | None during official trial |
| Payload retention | Payload remains on platform |
| Structure | Freestanding and functional |
Design Freedom
What Your Team Gets to Decide
Structure
- Overall geometry
- Frame width and height
- Structural bracing
- Base design
Lift System
- Platform design
- Guide system
- Winch/drum design
- Cable/string routing
Power & Motion
- Motor location
- Gear ratio
- Gears, chain, sprockets, or pulleys
- Speed-versus-torque strategy
Rules
What You May Not Do
- Hold or stabilize the lift during an official trial.
- Touch the payload or platform while it is moving.
- Manually assist the motor, axle, drum, or lifting string.
- Change the standardized payload mass.
- Begin with the payload partially raised.
- Allow the payload to hang freely instead of using a guided platform.
- Use non-VEX structural components unless specifically approved.
If the lift jams, tips, drops the payload, or requires assistance, the trial is unsuccessful.
Before You Build
Document Your Design
Before building, document your proposed lift using detailed concept sketches or a CAD model. A CAD model may be substituted for the detailed concept sketches as long as it clearly communicates the complete design. Your sketches or CAD model must clearly show and label:
- overall lift structure
- payload platform
- vertical guide system
- motor location
- power-transfer system
- winch/drum or lifting mechanism
- planned gear ratio
- major structural bracing
Before building, your team should be able to explain how power travels from the motor to the payload.
Engineering Concepts
What You Should Be Thinking About
Gear Ratio
How will your ratio change output speed and torque?
Mechanical Advantage
Does your mechanism increase the force available to raise the payload?
Work
W = Fd
Use the payload force and vertical lift distance.
Power
P = W/t
Use the work performed and lift time.
Friction & Alignment
Look for rubbing, binding, uneven winding, or platform tilt.
Structure & Load Path
Follow how the payload force travels through the cable, frame, bracing, and base.
Official Testing
Three Consecutive Trials
Start each trial with the platform at the LOW position and the complete 500 g payload resting on it. Remove your hands before the test begins. Timing starts when the motor begins moving and stops when the payload reaches the required height.
| Trial | Payload | Lift Height | Lift Time | Success? |
|---|---|---|---|---|
| 1 | 500 g | _____ mm | _____ s | Yes / No |
| 2 | 500 g | _____ mm | _____ s | Yes / No |
| 3 | 500 g | _____ mm | _____ s | Yes / No |
Iteration
Required Design Revision
Your first working design is not automatically your final design. Identify at least one problem, make a meaningful engineering revision, and document the change.
Possible issues include platform tilt, motor stalling, slow lifting, frame flex, gear skipping, uneven string winding, binding, base instability, excessive friction, or unnecessary mass.
Submission
What You Will Submit
- Initial detailed concept sketches or CAD model
- Completed VEX cargo lift
- Gear ratio and/or mechanical-system explanation
- Three-trial testing data
- Average lift time
- Work calculation
- Power calculation
- One problem observed during testing
- One documented design revision
- Final reflection: Explain the most important tradeoff your team made between speed, torque, stability, and reliability.