In order to provide disaster relief (DR) to waterfront locations, MEMA
disaster response equipment and emergency supplies can be loaded into
shipping containers and moved by water to anywhere in the Chesapeake
bay. In addition to the standard equipment, the team carries electrical
generators, water purification equipment, and enough food to supply
5,000 people for 1 month. This material can be loaded into 48
international standard shipping containers. These containers are 40 feet
long, 8 feet wide and 10 feet high.
Your task is to design a barge
to carry these 48 containers. The place that the barge will be moored
limits the length to 240 feet and the draft to 15 feet. The containers
are carried on top of the barge and they must be at least 5 feet above
the water. This distance is the freeboard.
You will build a model of your barge and test it in a tow tank
carrying model shipping containers to determine which barge goes fastest
over a range of towing forces.
To meet the requirements of this challenge you will:
Choose a length and a beam for your barge.
Determine a cargo configuration that fits this shape.
Predict the draft (T) of this barge.
Determine if the design has positive stability (GM of 0.5 inches is required). Make changes if needed to meet this requirement.
Construct the barge of readily available material such as pink
insulation foam. Shape the barge to minimize resistance and maximize
Tow the barge in a tow tank with towing forces of 2, 3, 4, 5, and 6
ounces. For each towing force, time the barge traveling 6 feet and use
this time to calculate the speed (V = Distance/Time) of the barge in
feet per second.
Plot the speed versus towing force. Find the area under the curve between 2 and 6 ounces using Simpson's rule.
Area = (1 /3)(1 ounce)(1*V2 + 4*V3 + 2*V4 + 4*V5 + 1*V6)
Make changes and retest to maximize this Area.
Demonstrate your knowledge of the engineering design and
development process and explain how you used this process to solve this
problem in a written report in the specified format. Include your calculation of stability and any drawings that you made.
Enhancement: Plot a Power versus Speed curve for your barge.
Model shipping containers are 4 inches long, 1 inch high and 1 inch
wide. They weigh between 1 and 3 ounces each. 48 of these containers
must be carried on top of the barge in any configuration desired except
that the containers cannot be stood on end. There are also half-sized
containers that are 2 inches long, 1 inch high and 1 inch wide.
Half-sized containers may be substituted for full-sized containers, two
Your model can be no more than 24 inches long. The containers must be
carried at least ˝ inch above the surface of the water (the model must
have at least ˝ inch of freeboard). The maximum allowed draft is 1 ˝
The barge must not tip over or ship water during testing.
The evaluation of the task will be based on the following:
_____ Product – DR Barge (10 points)
Well constructed to close tolerances. Design matches plans.
An innovative, correct, detailed, and well-engineered solution.
Light, efficient, and sound structure. No wasted material.
_____ Performance – Area under the force v. speed curve (20 points)
Based on your area compared to the maximum in the lab
20 Points – Maximum in lab
18 Points – 90% of maximum
16 Points – 80% of maximum
14 Points – 70% of maximum
12 Points – any barge tested
_____ Report (20 points)
Provide a written report in the specified format. The report will be
evaluated based on content, organization, style, and presentation. The
report must include your calculation of stability and any design
Here is some help with the report
Summary. The goal of the Disaster Relief Barge Challenge is to... Our barge... The best design would be...
Introduction—Introduce the challenge and explain the STEM involved
First, the rules of the challenge. Include all constraints.
How is your barge tested? What is the performance criteria with which your barge will be judged?
Explain all of the terms associated with ship geometry.
Explain how to find the draft using Archimedes' principle.
Explain how to calculate GM and explain what it is and how it is a measure of ship's stability.
Explain how to calculate the area under a curve using Simpson's Rule.
Describe the factors in resistance and how this information might be used to optimize your design.
Details—Tell the story of your design and construction from the beginning.
The first thing you did was to pick a length.
Then you determined the minimum beam for a draft of 1˝ inches.
When you learned about stability you discovered that you had to
increase your beam to be stable. Include your calculations or
Then you constructed your first barge. Can you include a sketch of your barge?
Then you tested your barge and determined your performance (area
under the curve) and compared it to others in the class. Be sure and
include your graph of Speed vs. Force. If you graphed Power vs. Speed,
include that too.
After that, you redesigned, modifed or rebuilt, and retested your
barge until your performance was optimized within the time allowed.
Describe each change and its effect on performance.
What was your best result?
What did you learn in this challenge?
If you could start over, what would your next design be?