Difference between revisions of "Sandbox/Boat"

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= Objectives =
= Objectives =
The objective of this lab is to design and build a a small vessel that floats on water. This is a competition lab that will be judged by a ratio that uses cost and payload. In theory, the design should maximize the non-structural weight (payload) that the balloon can lift and the time it can spend aloft while minimizing the boats's structural weight and its cost. In practice, other design choices could also win the competition. Consider the components of the ratio and the rules before designing the boat.
The objective of this lab is to design and build a small vessel that floats on water. This is a competition lab that will be judged based on a ratio that uses cost and payload. In theory, the design should maximize the non-structural weight (payload) that the boat can lift and the time it can spend afloat, while minimizing the boat's structural weight and its cost. In practice, other design choices could also win the competition. Consider the components of the ratio and the rules before designing the boat.


= Overview =
= Overview =
Boats are lighter-than-water vessels. They are widely used for recreation, military, touring, and commercial purposes. Boats range widely in size, shape, materials, and design, ranging in everything from a single person kayak to a shipping boat that can hold up to 25000 tons of cargo. Your goal is to design and optimize a boat to hold as much cargo as possible while still making the boat as lightweight as possible.
Boats are lighter-than-water vessels. They are widely used for recreation, military, touring, and commercial purposes. Boats range widely in size, shape, material, and design, ranging in size from a single person kayak to a shipping boat that can hold up to 25000 tons of cargo. Your goal is to design and optimize a boat to hold as much cargo as possible while still making the boat as lightweight as possible.
 
[[Image:Stable Boat(2).jpg|500px|thumb|center||Figure 1: Stable Boat.]]
 
[[Image:Stable Boat(2).jpg|500px|thumb|center||Figure 2: Stable Boat.]]


The Principle of Archimedes and Newton's Second Law of Motion explain how these vessels float.
The Principle of Archimedes and Newton's Second Law of Motion explain how these vessels float.
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A boat will float if the weight of the water being displaced is equal to or greater than the weight of the boat.
A boat will float if the weight of the water being displaced is equal to or greater than the weight of the boat.


The Principle of Archimedes can be expressed in an equation, which is more useful for engineering calculations.
The Principle of Archimedes can be expressed in an equation, which is more useful for engineering calculations.
 
From the definition of density (''ρ ='' mass / volume ''= m / V''), Newton's Second Law of Motion (''F = ma''), and for the acceleration due to gravity (''a = g''), the gravitational force on a volume of fluid is ''F = m*a = (ρV)(g)''. You can also calculate force using the definition of pressure, where pressure equals force divided by area (''P=F/A''), therefore force equals pressure times area (''F=P*A''). From here, pressure can be defined as hydrostatic pressure, which is equal to the gravitational force of acceleration (g) multiplied by the height (h) and density (''ρ''). There are a few ways that the buoyant force can be calculated; these equations can help you think of ways to optimize the design of your boat:
 
<center>F<sub>buoyant</sub> = F<sub>up</sub> - F<sub>down</sub>
 
F<sub>buoyant</sub> = (PA)<sub>up</sub> - (PA)<sub>down</sub>
 
F<sub>buoyant</sub> = pgAh<sub>bottom</sub> - pgAh<sub>top</sub>
 
F<sub>buoyant =pgA(h<sub>bottom</sub> - h<sub>top</sub>)</center>


From the definition of density (''&rho; ='' mass / volume ''= m / V''), Newton's Second Law of Motion (''F = ma''), and for the acceleration due to gravity (''a = g''), the gravity force on a volume of fluid is ''F = m*a = (&rho;V)(g)''. You can also calculate force using the definition of pressure where pressure equals force divided by area (''P=F/A''), therefore force equals pressure times area (''F=P*A''). From here pressure can be defined as hydrostatic pressure which is equal to the gravitational force of acceleration (g), multiplied by the height (h) and density (''&rho'').


F_buoyant = F_up - F_down
== The Boat Competition Ratio ==
This lab is a competition. The boat competition ratio will be used to measure the performance of each design.


F_buoyant = pgAh_bottom - pgAh_top
<math>Design\ Ratio = \frac{Weight\ Supported}{Boom\ Weight} \times \frac{60\left[\text{s}\right]}{Anchor\ Time\left[\text{s}\right]+30\left[\text{s}\right]} \times \frac{Boom\ Length\left[\text{m}\right]}{1.5\left[\text{m}\right]}\,</math>


F_buoyant =pgA(h_bottom-h_top)


== The Balloon Competition Ratio ==
<math>Competition\Ratio = \frac{Payload}{Cost*Weight of the Boat}\,</math>
This lab is a competition. NASA will judge the design's performance against the other designs in the section. The balloon competition ratio will be used to measure the performance of each design.


<math>\frac{TimeAfloat[s]}{Cost[$]} \divide Payload\,</math>


''Payload'' is the number of paperclips the design can lift. Time afloat is the elapsed time from when the balloon rises to when it returns to its starting position. Cost is the cost to build the balloon.
''Payload'' is the mass the design can lift before sinking a total of 2 inches. The weight of the boat is taken before it is placed in the water. The cost is the cost of the boat calculated from the materials price list.  


The design will be allowed three trials.
The design will be allowed only ONE trial.


= Competition Rules =
= Competition Rules =
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* All the materials used in the design must be purchased
* All the materials used in the design must be purchased
* Unused materials may not be returned for credit
* Unused materials may not be returned for credit
* The maximum balloon volume is 1 m<sup>3</sup>
* The maximum boat size is 1 ft<sup>3</sup>
* Time aloft is the elapsed time from when the balloon rises from its initial height to when it sinks to that height
* The design is limited to ONE trial
* If the balloon does not rise, the time aloft is zero
 
* The design is limited to three trials. Indicate the number of trials performed and the ratios in the Abstract of the lab report. The lab report should also show the results for each trial including dimensions, payload, estimated balloon volume, and competition results


= Design Considerations =
= Design Considerations =
* Which balloon shape best minimizes structural mass and effectively captures and retains warm air to fill and launch the balloon?
* How is the boat volume maximized and weight minimized?
* How is balloon volume maximized and surface area minimized?
* Carefully consider weight, surface area, volume, material properties, and cost in the design process.
* Carefully consider weight, surface area, volume, material properties, and cost in the design process.


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== Materials with Price List ==
== Materials with Price List ==
* Drawing paper: $0.10/sheet
* Drawing paper: $0.10/sheet
* Aluminum foil: $0.15/foot
* Plastic wrap: $0.05/foot
* Tissue wrap: $0.10/sheet
* Tissue wrap: $0.10/sheet
* 8 ½ x 11 paper sheets: $0.05/sheet
* 8.5" x 11" paper: $0.05/sheet
* Kevlar string: $0.05/30cm
* Kevlar string: $0.05/foot
* Adhesive tape: $0.03/30cm
* Adhesive tape: $0.03/foot
* Plastic straws: $0


== Equipment Used ==
== Equipment Used ==
* Scissors
* Scissors
* A glue stick
* A glue stick
* Paper clips
* A personal heater
* A stop watch
* A stop watch
* A thermometer


= Procedure =
= Procedure =
Construct a hot air balloon using the available materials. This lab is a competition. The design with the highest ratio of payload divided by cost multiplied by time afloat will be  the winner.
Your goal is to construct a boat using the available materials. This lab is a competition. The design with the highest competition ratio wins.
 
Sketch a preliminary design. The maximum balloon volume is 1 m<sup>3</sup>. Volume should be approximated and recorded on your lab notes.
 
The design must include an area near the bottom of the balloon where paperclips may be attached  to add payload during the competition phase of the lab. In addition, there must be an opening that will allow hot air to enter the balloon  when placed over the heater.


'''<span style="color: red">WARNING:</span> Turn the heater off when not in use. Otherwise, it will become extremely hot and possibly melt the balloons.'''
Sketch a preliminary design. The maximum boat size is 1 ft<sup>3</sup>. Volume should be approximated and recorded in your lab notes. You or someone in your group will be in charge of adding weights. If you reach a point where no more weights can be added without them falling into the water, then that will be the end of the trial.  


When finished, have the sketch approved and signed by the lab TA. Construct the balloon using the materials that were selected. For the competition phase, a payload will be attached to the bottom of the balloon and it will be filled with hot air.
When finished, have the sketch approved and signed by a Lab TA. Construct the boat using the materials that were selected. For the competition phase, a payload will be placed in the boat after the boat has been placed in the water. A TA must be present for the trial, and the TA will weigh the boat before it is placed in the water.


The lab work is now complete. Please clean up the workstation. Return all unused materials to the TA.
The lab work is now complete. Please clean up the workstation. Return all unused materials to the Lab TA.


= Assignment =
= Assignment =


== Individual Lab Report ==
== Individual Lab Report ==
<!--
Follow the lab report guidelines laid out in the page [[Specifications for Writing Your Lab Reports]] in the ''Technical Communication'' section of this manual. The following discussion points should be addressed in the appropriate section of the lab report:
:''For EG1003 sections, this report is '''optional''' and will count as a Bonus Lab Report if submitted. Extra credit will be applied to the PowerPoint presentation since the report is optional.''
* Discuss the importance of boats today.
:''For EGED sections, this report is '''required''' and will count as a regular lab report.''
* Describe the rules of the competition in the Introduction. What consequences did the rules have on design decisions? In answering, use the appropriate equations.
-->
* Describe the boat's design. Calculate the volume of the boat (i.e. dimensions and calculation) to show compliance with the rules. Explain the design choices. Include a discussion of the materials chosen and why. Explain the strategy for winning the competition.
 
* Describe how the design succeeded or failed. What choices could have improved the boat's final standing in the competition?
Follow the lab report guidelines laid out in the page called [[Specifications for Writing Your Lab Reports]] in the ''Technical Communication'' section of this manual. The following discussion points should be addressed in the appropriate section of the lab report:
* Discuss and elaborate on how to improve the competition ratio for your design.
* Discuss the importance of hot air balloons today
* Suggest possible improvements in conducting the lab.
* Describe the rules of the competition in the Introduction. What consequences did the rules have on design decisions? In answering, use the appropriate equations
* Include the spreadsheet with every boat's results. Describe the results and discuss the other designs in the class.
* Explain the Ideal Gas Law and the Principle of Archimedes. Include a definition and an example of each
* Describe the balloon's design. Calculate the volume of the balloon (i.e., dimensions and calculation) to show compliance with the rules. Explain the design choices. Include a discussion of the materials chosen and why. Explain the strategy for winning the competition
* Describe how the design succeeded or failed. What choices could have improved the balloon's final standing in the competition?
* Discuss and elaborate how to improve the competition ratio for this design.
* Suggest possible improvements in conducting the lab
* Include the spreadsheet with every balloon's results. Describe the results and discuss other designs in the class


{{Lab notes}}
{{Lab notes}}


== Team PowerPoint Presentation ==
== Team PowerPoint Presentation ==
The following discussion points must be addressed in the appropriate section of the presentation:
There is NO team PowerPoint for Lab 1.
* Describe the rules of the competition. What consequences did the rules have on design decisions? Use the appropriate equations in the answer.
* Since one term in the competition ratio is cost, present the cost of the balloon. Use the page [[How to Show Cost Data in Presentations]] for instructions on how to do this.
* Explain the Ideal Gas Law and the Principle of Archimedes. Include a definition and an example of each.
* Were all materials purchased used?
* Describe the balloon's design. Show the volume of the balloon (i.e., dimensions and calculation) to show compliance with the rules. Explain the design choices. Discuss the materials chosen and why they were chosen. Explain the strategy for winning the competition.
* Describe how the design succeeded or failed. What choices could have improved the balloon's final standing in the competition?
* Discuss how to improve the competition ratio.
 
= Endnotes =
# National Aeronautics and Space Administration. 2017. “Scientific Balloons.” Accessed 20 August 2017 from  https://www.nasa.gov/scientificballoons
{{Reflist}}


{{Laboratory Experiments}}
{{Laboratory Experiments}}

Latest revision as of 16:24, 23 June 2019

Objectives

The objective of this lab is to design and build a small vessel that floats on water. This is a competition lab that will be judged based on a ratio that uses cost and payload. In theory, the design should maximize the non-structural weight (payload) that the boat can lift and the time it can spend afloat, while minimizing the boat's structural weight and its cost. In practice, other design choices could also win the competition. Consider the components of the ratio and the rules before designing the boat.

Overview

Boats are lighter-than-water vessels. They are widely used for recreation, military, touring, and commercial purposes. Boats range widely in size, shape, material, and design, ranging in size from a single person kayak to a shipping boat that can hold up to 25000 tons of cargo. Your goal is to design and optimize a boat to hold as much cargo as possible while still making the boat as lightweight as possible.

Figure 1: Stable Boat.
Figure 2: Stable Boat.

The Principle of Archimedes and Newton's Second Law of Motion explain how these vessels float.

Principle of Archimedes and Newton's Second Law of Motion

The Principle of Archimedes states that when a body is immersed in a fluid (a liquid or a gas), an upward force is exerted on the body that is equal to the weight of the fluid the body displaces. This upward force is called buoyancy.

A boat will float if the weight of the water being displaced is equal to or greater than the weight of the boat.

The Principle of Archimedes can be expressed in an equation, which is more useful for engineering calculations.

From the definition of density (ρ = mass / volume = m / V), Newton's Second Law of Motion (F = ma), and for the acceleration due to gravity (a = g), the gravitational force on a volume of fluid is F = m*a = (ρV)(g). You can also calculate force using the definition of pressure, where pressure equals force divided by area (P=F/A), therefore force equals pressure times area (F=P*A). From here, pressure can be defined as hydrostatic pressure, which is equal to the gravitational force of acceleration (g) multiplied by the height (h) and density (ρ). There are a few ways that the buoyant force can be calculated; these equations can help you think of ways to optimize the design of your boat:

Fbuoyant = Fup - Fdown

Fbuoyant = (PA)up - (PA)down

Fbuoyant = pgAhbottom - pgAhtop

Fbuoyant =pgA(hbottom - htop)


The Boat Competition Ratio

This lab is a competition. The boat competition ratio will be used to measure the performance of each design.


Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle Competition\Ratio = \frac{Payload}{Cost*Weight of the Boat}\,}


Payload is the mass the design can lift before sinking a total of 2 inches. The weight of the boat is taken before it is placed in the water. The cost is the cost of the boat calculated from the materials price list.

The design will be allowed only ONE trial.

Competition Rules

The following rules must be observed at all times during the competition. Violation of any of these rules will result in the disqualification of the balloon:

  • The TA must approve the design before it can be entered in the competition
  • All the materials used in the design must be purchased
  • Unused materials may not be returned for credit
  • The maximum boat size is 1 ft3
  • The design is limited to ONE trial


Design Considerations

  • How is the boat volume maximized and weight minimized?
  • Carefully consider weight, surface area, volume, material properties, and cost in the design process.

Materials and Equipment

Materials with Price List

  • Drawing paper: $0.10/sheet
  • Aluminum foil: $0.15/foot
  • Plastic wrap: $0.05/foot
  • Tissue wrap: $0.10/sheet
  • 8.5" x 11" paper: $0.05/sheet
  • Kevlar string: $0.05/foot
  • Adhesive tape: $0.03/foot

Equipment Used

  • Scissors
  • A glue stick
  • A stop watch

Procedure

Your goal is to construct a boat using the available materials. This lab is a competition. The design with the highest competition ratio wins.

Sketch a preliminary design. The maximum boat size is 1 ft3. Volume should be approximated and recorded in your lab notes. You or someone in your group will be in charge of adding weights. If you reach a point where no more weights can be added without them falling into the water, then that will be the end of the trial.

When finished, have the sketch approved and signed by a Lab TA. Construct the boat using the materials that were selected. For the competition phase, a payload will be placed in the boat after the boat has been placed in the water. A TA must be present for the trial, and the TA will weigh the boat before it is placed in the water.

The lab work is now complete. Please clean up the workstation. Return all unused materials to the Lab TA.

Assignment

Individual Lab Report

Follow the lab report guidelines laid out in the page Specifications for Writing Your Lab Reports in the Technical Communication section of this manual. The following discussion points should be addressed in the appropriate section of the lab report:

  • Discuss the importance of boats today.
  • Describe the rules of the competition in the Introduction. What consequences did the rules have on design decisions? In answering, use the appropriate equations.
  • Describe the boat's design. Calculate the volume of the boat (i.e. dimensions and calculation) to show compliance with the rules. Explain the design choices. Include a discussion of the materials chosen and why. Explain the strategy for winning the competition.
  • Describe how the design succeeded or failed. What choices could have improved the boat's final standing in the competition?
  • Discuss and elaborate on how to improve the competition ratio for your design.
  • Suggest possible improvements in conducting the lab.
  • Include the spreadsheet with every boat's results. Describe the results and discuss the other designs in the class.

Remember: Lab notes must be taken. Experimental details are easily forgotten unless written down. EG1004 Lab Notes Paper can be downloaded and printed from the EG1004 Website. Use the lab notes to write the Procedure section of the lab report. At the end of each lab, a TA will scan the lab notes and upload them to the Lab Documents section of the EG1004 Website. One point of extra credit is awarded if the lab notes are attached at the end of the lab report. Keeping careful notes is an essential component of all scientific practice.

Team PowerPoint Presentation

There is NO team PowerPoint for Lab 1.