CONTEXT:

Throughout the history of the world, humankind has endured numerous destructive wars. While war was never a desirable choice for civilizations, societies have always felt compelled to be prepared for an attack. This constant pursuit of preparedness has produced numerous technological advances. One such innovation was the catapult.

Ancient Greeks and Romans were the first to perfect this device. Their catapults were capable of throwing a 60-pound rock further than the distance of five football fields. It took great ingenuity and skill to design and build a device that harnessed such a tremendous amount of energy.

Modern catapults are based upon design principles derived from the early Greek and Roman catapults.  For example, the massive steam catapults used to launch aircraft from carriers at sea are adaptations of these principles.  By providing a rapid controlled energy source and the right angle of launch, objects can be thrown long distances with amazing accuracy.

CHALLENGE:

EXPLORATORY
Research and model a historical catapult that is capable of launching a penny at least 10 meters.

INTERMEDIATE
Research and construct a model of a working catapult. Your design must be able to launch a load (Ping-Pong ball) from a tabletop onto a 600 mm diameter target (box) placed at least three (3) meters away on the floor.
 
ADVANCED
Research, design and construct a catapult that will launch various loads (pennies, etc.) from a table top into a 15cm diameter container located five (5) meters away on the floor.

MATERIALS:

EXPLORATORY, INTERMEDIATE, ADVANCED

• Cardboard
• Paper, various weights/colors
• Plastic spoons
• Rulers/Tape measures
• Masking tape
• Rubber bands
• Craft sticks/Balsa wood
• Kite string
• Scissors, glue, fasteners
• Box for target
• 1-land saws/Drills/Wood files
• Finishing nails
• Straight pins
• X-acto knife
• Protractors
• Compass
• Pennies
• Ping-Pong ball
• 15cm diameter container
• Additional found objects and/or materials from home

CRITERIA:

Your success on this Challenge will be based on your completion of the activities below. Three general criteria for your performance will be: your participation in the activity; the accuracy of your measurement and model construction; and the performance of your design.  Your teacher will help you understand how your performance will be graded.

EXPLORATORY

• Locate and document several examples of catapults from the past.
• Write a brief paragraph that summarizes the historical contribution(s) to civilizations that catapults provided.
• Choose a historical catapult model; develop an explanation of the mechanics of its operation.
• Construct a working model of the selected catapult; include sketches and drawings.
• Test and present your design.

INTERMEDIATE

• Research catapults and other war machines from the past.
• Summarize the history and mechanics of a specific catapult.
• Construct a working model of the chosen catapult using only the materials provided; be sure to include sketches and drawings.
• Conduct tests to acquire Performance Data (range and accuracy); chart results.
• Test the accuracy of the design; predict the range of the evaluation toss.
• Present your design.

ADVANCED

• Research catapults and other war machines from the past.
• Summarize the history and mechanics of different catapults.
• Develop a design that provides an adjustable angle of launch and a triggering mechanism.
• Construct a working model of the chosen catapult using only the materials and specifications provided; be sure to include sketches and drawings.
• Conduct tests to acquire Performance Data (maximum height of launch, maximum range and accuracy); chart the results.
• Use the Performance Data to predict the distance of each launch; compare the prediction to actual results.
• Present your design.