Catapult Project
Background:
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:
Beginner
Research and model a historical catapult that is capable of launching a marshmallow at least 10
meters.
NEXT LEVEL
Research and construct a model of a working catapult. Your design must be able to launch a load
(marshmallow) from a tabletop onto a 600 mm diameter target (box) placed at least three (3) meters
away on the floor.
LOOK OUT!
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:
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Cardboard, paper - various weights
Rulers/Tape measures
Weights if necessary for your type of catapult, provided by Mr. Hendricks
Rubber bands
Kite string
Scissors, glue,
Protractors
Compass
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. A rubric will be provided
to guide you through the development process.
BEGINNER
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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 using only the materials provided; include
sketches and drawings.
Test and present your design.
NEXT LEVEL
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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 and accuracy of the toss.
Present your design.
LOOK OUT
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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.
Books at WUHS
623 Gra
623 Ric
623.409 DeV
R 608 Wor
R 603 IL
Eyewitness Castle (contains pictures and descriptions of medieval siege
weapons including catapults and trebuchets)
Weapons: Designing the Tools of War (use index at back to
look up catapults)
Medieval Weapons: An Illustrated History of Their Impact (use
index at back to look up catapults and trebuchets)
World of Invention: History’s Most Significant Inventions and People Behind Them\ (use index at back to look up
catapults)
How It Works: Illustrated Encyclopedia of Science and Technology: volume 4 (discusses steam catapults)
Online Services
ELibrary (log-in name: 90-10026 password: Bigchalk)
Suggested search phrases (do use asterisks): Catapult* and physics
Construct* and catapult*
Internet Public Library - subject – trebuchet - “The Grey Company Trebuchet Page”
Internet Sites
http://www.howstuffworks.com/question127.htm
Great site – Includes information on force, power, torque, and energy of catapults; how to build a catapult, physics of the trebuchet,
algorithmic beauty of the catapult; and more
http://apphysicsb.homestead.com/catapult.html
Another excellent, comprehensive site – includes links to information about how a catapult works, how to build one, trebuchet physics, the
history of the trebuchet, war engines of the middle ages, catapults, catapult simulation, etc.
http://www.stormthecastle.com/trebuchet/how-to-build-a-trebuchet.htm
Plans and pictures on how to build a medieval trebuchet
http://howtomakeatrebuchet.com/blog/
Good site with details about how to build the various parts of a trebuchet
http://tuhsphysics.ttsd.k12.or.us/Research/IB05/AsaiGrafPete/index.htm
Contains a physics experiment regarding the manipulation of arm length on a catapult, with photos and links to helpful, additional
resources
http://news.nationalgeographic.com/news/2004/02/0205_040205_catapults.html
Contains information on the history and historical uses of catapults as well as some discussion about mathematical principles applied to
catapult construction
http://depts.washington.edu/chinaciv/miltech/catapult.htm
Contains information on different types of catapults with diagrams
http://members.iinet.net.au/~rmine/gctrebs.html#danes
Contains everything you could want to know about medieval trebuchets
http://www.instructables.com/id/The-Office-supplies-trebuchet/
How to build a trebuchet with office supplies
http://www.instructables.com/id/How-to-Make-a-Medieval-Trebuchet-Out-of-Cardboard/
How to build a trebuchet out of cardboard
http://www.pbs.org/wgbh/nova/lostempires/trebuchet/builds.html
NOVA builds a trebuchet video
GAMES
http://www.globalspec.com/trebuchet/
The Treb Challenge – Custom build your trebuchet to take on three separate challenges: distance, accuracy, and power
http://science.discovery.com/tv-shows/punkin-chunkin/punkin-chunkin-game.htm
Punkin Chunkin game via Discovery Channel
Beginner – Highest possible grade = C
Beginner
Research
- historical contributions
Catapult Explanation
- mechanics of operation
Design Explanations
Unsatisfactory (Grade range: F)
Satisfactory (Grade range: D – C)
Exemplary (Grade range: B – A)
-Student used single resource to find information.
-Didn’t cite resources.
-One type of catapult listed.
-Less than a paragraph of information.
-Information hand written.
-Student turns in no explanation of mechanics of chosen
catapult.
-Students used multiple resources and cited.
-Information encompassed a paragraph.
-Two catapults listed.
-Information hand written or typed with errors.
-Student used multiple resources from multiple media sources and
cited each source.
-More than 2 types of catapults listed.
-Written information exceeds a paragraph, is typed, has a title
page and is grammatically correct.
-Student turns in explanation of mechanics of chosen catapult.
-Student demonstrates correlation of explanation to working model.
-Explanations are typed
-Accurate and updated sketches are provided.
-Model is an accurate representation of initial sketch.
-No sketches are provided
-Student turns in incomplete explanation of mechanics of
chosen catapult.
-Explanation is handwritten
-Sketches are provided but are not accurate.
-Student does not test catapult or present to the class
-Student tests or presents catapult to the class
-Student tests and presents catapult to the class.
Unsatisfactory (Grade range: F)
Satisfactory (Grade range: D – C)
Exemplary (Grade range: B – A)
-Student used single resource to find information.
-Didn’t cite resources.
-One type of catapult listed.
-Less than a page of information.
-Student turns in little or no explanation of mechanics
of chosen catapult.
-Information is hand written.
-Student had incomplete working model or could not have
repeated attempts.
-No sketches are provided
-Performance tests are conducted but not recorded
-Students used multiple resources and cited.
-Information encompassed at least a page.
-At least two catapults listed.
-Student turns in explanation of mechanics of chosen catapult.
-Explanation is handwritten or typed errors.
-Multiple performance tests are conducted and recorded for
range or accuracy.
-Student used multiple resources from multiple medias.
-Cited each sources.
-More than 2 types of catapults listed.
- Included explanation of mechanics of chosen catapult.
-Student demonstrated correlation of explanation to working model.
-Written information exceeds one page, is typed, has a title page and
is grammatically correct.
-Student’s model worked with ability to have multiple attempts.
-Accurate and updated sketches are provided.
-Model is an accurate representation of initial sketch.
-Multiple performance tests are conducted and recorded for both
range and accuracy.
-Does not do accuracy tests.
-Accuracy tests are done but data is not accurately taken
or is not displayed neatly.
-Predictions and tests are done for toss range and accuracy.
-Data is recorded accurately and neatly.
-Students does not present design to class
-Students presents design to class
-Student presents and thoroughly explains design elements of
catapult to the class.
– sketches and drawings
Test and Presentation
Next Level – Highest possible grade = B
Next Level
Research
- historical contributions
- mechanics
Working Model
Performance Data Collection
– Accuracy and Range
Performance Tests
– Accuracy and Range
Presentation
-Student’s model worked.
-Sketches are provided but are not accurate.
Look Out – Highest possible grade = A
Look Out
Research
- historical contributions
- mechanics
Model Design
Working Model
Performance Data Collection
Unsatisfactory (Grade range: F)
Satisfactory (Grade range: D – C)
Exemplary (Grade range: B – A)
-Student used single resource to find information.
-Didn’t cite resources.
-One type of catapult listed.
-Less than 2 pages of information.
-Information hand written.
-No design depicting adjustable angle launch or triggering
mechanism
-Student had incomplete working model or could not have
repeated attempts.
-No sketches are provided
-Performance tests are not completed.
-Student used multiple resources and cited.
-Information encompassed 2 pages.
-Two catapults listed.
-Information hand written or typed with errors.
-Students failed to use performance test data to predict
accuracy, range, and height of tosses.
-Students used performance test data but results did not match
for some tests.
-Student used multiple resources from multiple media sources.
-Cited each source.
-More than 2 types of catapults listed.
-Written information exceeds 2 pages, is typed, has a title page and
is grammatically correct.
-Design for adjustable angle launch and triggering mechanism is
given and is used as shown on working model.
-Student’s model worked with ability to change range.
-Accurate and updated sketches are provided.
-Model is an accurate representation of initial sketch.
-Performance tests are completed and acquired data for toss
range, height, and accuracy.
-Data is recorded accurately and neatly.
-Students used performance test data and achieved matching
results for accuracy, range, and height.
-Students does not present design to class
-Students presents design to class
– Accuracy, Range, Height
Performance Predictions Tests
– Accuracy, Range, Height
Presentation
-Design for adjustable angle launch and/or triggering mechanism
given but not used on actual working model
-Student’s model worked.
-Sketches are provided but are not accurate.
-Some performance tests are completed but data is not
accurately taken or is not displayed neatly.
-Student presents and thoroughly explains design elements of
catapult to the class.