Uphill Struggle

Jack and Jill have made a luxury double-seater cart, but it is very heavy to push up the hill.

Can you design a way to stop the cart from rolling back down the hill when they stop to catch their breath?

Design and make a vehicle that:
• can carry at least 50 g (≈ 1.75 oz) (or approximately 1 weight brick)
• has a safety feature that does not prevent the vehicle from rolling forwards

1. Make a sketch of the idea you designed and made.
2. Label the three most important parts, explaining how they work.
3. Suggest three improvements.

Note: You are advised not to share this image with students.

Can the cart carry the weight of at least one weight brick?
Test to see, then add more weight. What are the criteria for success?
The cart should not break and the load should not rub against the wheels, etc.

Does it roll freely?
Set the hill at any slope angle you like, (e.g. 30 cm [≈ 12 in] high at one end of a 1 meter [≈ 1 yard] plank) and run the cart forwards down it. The further it rolls along the floor the better.

Does the auto stop feature work?
Turn the cart around without touching anything on board so it faces backwards down the hill. Let go! Does it stay still? Keep increasing the steepness until the cart slips. The steeper you can go before it slips, the better.

How safe and comfortable is your luxury cart?
Make two play dough riders with very smooth skin. Place them gently on the cart in whatever seats are supplied. Let the cart run down the hill until it stops. Now check the riders for bumps, cuts, and bruises – the less, the better.
How will they survive bumping over an all-terrain course?
Would your cart be a good ambulance?

Look at:

Fishing Rod

Freewheeling

Harness wind energy to help push the cart uphill. Make sure that the auto stop will stop it rolling down the hill again if the wind stops.

All Terrain Cart! Can you find a way to make the cart climb over rulers and maybe even pencils that are put in its way on the hillside?

Tip:
Create a means of storing things on board the cart.