2. Design and Engineer an Accurate Trebuchet

3. Anyone who has played Age of Empires will know exactly what a trebuchet is, and what it does. A trebuchet exists as a medieval rock throwing machine, but quite different to a catapult.

5. Trebuchet at the Tower of London

6. William the Conquerer needs help invading England and has hired you, a weapons master, to design and build a trebuchet for his siege on local castles. Luckily this is early England (1066 AD to be precise) and there are plenty of trees around to build plenty of trebuchets. Your challenge is to build a trebuchet that can launch a boulder 100 yards into the walls of the enemy castle walls. (ok, 4 feet) This will be far enough away to avoid the enemy archers on top of the wall shooting arrows at King Henry’s armies – and you too.

7. Should you succeed and King William is victorious, he will promote you to Knight of Weaponry, grant you a nice manor house with plenty of peasants who will earn you money while they farm the land.

8. The Little Trebuchet That Could (adapted from http://littletrebthatcould.tripod.com/id1.html) TREBUCHET PHYSICS Some physics concepts applicable to our trebuchet lab: Projectile motion- applicable to movement of ball in air Forces- a major factor in launching the projectile

9. The trebuchet is a first class lever. The force is applied to one end, the load is on the other end and the fulcrum sits between the two. Children playing on the see-saw is an example of the lever. If a child on one end is allowed to fall from a high place all the way to the bottom through circular motion, the other child will be launched into midair (provided the first child is heavier than the second).

10. With the lever type trebuchet, the fulcrum can be adjusted to change the performance of the trebuchet. If it is close to the weight and far from the projectile, it will require heavier weights, but it will also give great projectile distances.

11. Your arm works this way at the shoulder. The fulcrum is your shoulder, the projectile is the baseball, and the “force” is supplied by your muscles.

12. The sling is another application of physics. It is basically a piece of string tied to the projectile and attached to the arm, this gives the projectile extra hurling power coming off the arm. When throwing darts, your elbow is the fulcrum.

13. Gravity pulls the heavy counterweight down towards the ground. Because the counterweight is attached to the throwing arm on one side of the axle, the projectile side of the throwing arm is pulled upwards. The rate of movement on the right hand side is faster than the left hand side, due to the lever physics. The sling carrying the projectile is carried forwards by the lifting arm.

14. Engineers and computer designers often draw simple diagrams to demonstrate basic designs in order to communicate their ideas.

15. Monty Python trebuchet scenes http://us.yhs4.search.yahoo.com/yhs/search?hspart=Babylon&hsimp=yhs- 002&type=br112dm25ts161&p=monty%20python%20and%20the%20holy%20g rail%20trebuchet%20cow%20sceneshttp://us.yhs4.search.yahoo.com/yhs/search?hspart=Babylon&hsimp=yhs- 002&type=br112dm25ts161&p=monty%20python%20and%20the%20holy%20g rail%20trebuchet%20cow%20scenes (longer but less quality sound, first three minutes the most important) http://www.youtube.com/watch?v=9V7zbWNznbs (shorter but better sound, less funny stuff)

16. This is what you will be building. Can you identify the BASE, SWING ARM, COUNTER WEIGHT, and SLING?