1. Basic Physical Principles
EggXpress
Basic Physical Principles

2. The drop
6 stories
No parachute or wings allowed

3. Goals? Give it as much padding as you can?
Only use a few eggs to keep them safe?

4. Score Based on Surviving Eggs – Total Eggs(0.25)
Score = S.E. – T.E.(0.25)

5. Score (cont)
As you can see, if you have a survival rate of ½, using more eggs is always better.

6. Score (cont)
As you can see, having more eggs survive is better for your score, no matter how many eggs you used.

7. Score (the issue)
YOU have to determine where the balance is for you between additional eggs, and when the % of destroyed eggs becomes too high.
Obviously, there is a point in every design where more eggs will lead to more destruction than benefit.

8. How do you get more eggs? Shape of package.
The best shape for the most eggs is a sphere, since the package can’t be larger than 10cm in any direction. A box leaves too much room at the edges.
We can fill in the blue with more eggs, or padding!
10cm

9. The problems with sphere:
Pretty aerodynamic.
Will fall FAST and hit HARD
Harder hit = more destruction

10. POSSIBLE Solution: Cut off bottom of sphere.
Have roominess for eggs and stuffing above, bottom resists air to slow down package.

11. Save the Eggs
Slow down package as much as possible based on its shape.
Slow down the impact as much as possible with cushion.

12. Math
(F)(t) = change in momentum. The change in momentum will be made smaller by reducing the package’s speed. The only other way to reduce the force is to increase the time (t) taken for the crash itself.

13. Increase collision time:
Add cushioning.
Get a cushion that absorbs all impact energy.
You can determine this by bouncing a golf ball on the cushion. Less bounce for the ball means more energy absorbed by the cushion.
Best cushion is tempurpedic material.
Get by asking local mattress stores for their samples for an engineering project.

14. What do you think?
Write down 5 summarizing sentences about different things you’ve learned.
Write down or draw 3 ideas this gives you.
Share you ideas with someone else who has viewed this powerpoint.