Hands-on Activity Swiss Alps Emergency Sled Design

Learning Objectives

After this activity, students should be able to:

• Research scientific resources.
• Sketch a sled design.
• Create and build a prototype sled.
• Demonstrate tests for speed and distance.
• Describe what a natural disaster is.
• Discuss safety issues.
• Complete a technical report. 
• Calculate speed of an object when given distance and time.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

NGSS: Next Generation Science Standards - Science

Common Core State Standards - Math

International Technology and Engineering Educators Association - Technology

State Standards

Materials List

Each group needs:

• Appendix A: Pre/Post Quiz (one per student)
• Appendix C: Student Performance Rubric (one per group)
• Appendix D: Engineering Prototype Brainstorming Design (one per group)
• Appendix E: Speed Calculation Worksheet (one per student)
• Appendix F: Differentiated Speed Calculation Worksheet (one per student, as needed)
• Appendix G: Technical Report Template (one per group per day)
• Appendix H: Engineering Log (one per group)
• Appendix J: Final Technical Report (one per group)
• stopwatch (or a smartphone timer)
• calculator

For the class to share (assuming class size of 25):

• ramp (thick poster board; 0.5  x  0.75 m) and supporting material (suggested: books, chair, small table, to angle the ramp)
• protractor (for setting up the ramp at a given angle)
• various recycled materials such as
• aluminum cans (10)
• water bottles (10)
• sandwich bags (50)
• plastic cups (50)
• aluminum foil (2.75 sq. m)
• plastic wrap (10 sq. m)
• Popsicle™ sticks (100)
• cotton balls (100)
• additional materials students may bring in (will vary)
• rulers (10)
• peanut packing (50) 
• Appendix B: Description of Engineering Design Challenge
• Appendix K: Materials List (one per class)

Worksheets and Attachments

Introduction/Motivation

When thinking about the science of sledding, multiple factors need to be accounted for. One consideration is Newton’s first and second laws of motion: an object at rest stays at rest unless acted upon by an outside force; the force (F) on an object is related to the mass (m) and acceleration (a) of the object, or F=ma. Without an outside force, a sled at rest stays at rest and will not accelerate. Another important factor is friction as it impacts the sled speed. Finally, gravity is another factor to consider when thinking about sledding. This attraction force is present while sledding and pulls the sled down the hill.

What is a natural disaster? Can you think of a few examples? (Elicit student responses). Explain that a natural event such as a flood, earthquake, or hurricane that causes great damage or loss of life.

(Present the engineering challenge to the class.) The Swiss Seismological Service records 500 to 800 earthquakes per year. Recently, Switzerland was struck by a magnitude 6.0 earthquake. A road near the epicenter in the Swiss Alps was heavily damaged, cutting off a town’s supply line. Your engineering firm has been selected to use the engineering design process (EDP) to help the Swiss design a sled that can bring resources and supplies to the town while the road is being repaired.

(Explain the requirements for the design challenge.) The government will select the prototype sled design that optimizes speed, can go the farthest distance, and is durable enough to carry resources across rugged terrain.

(Explain the sled testing.) Each sled will be tested on a ramp and collide into a barrier to see whether the sled can hold the material safely. The sleds will also go through three separate tests to determine safety, speed, and distance. The safety test results will use a three-point scale: One point will be awarded to the sleds that hold the given material through the speed test. Two points will be awarded to the sleds that can hold material throughout the speed and distance test. Finally, three points will be awarded to the sleds that can hold material throughout each test combined.

Since we will be designing our sled in the U.S., we need to convert our testing data (speed and distance) into the metric system for the Swiss government. You will work in teams of four for this engineering design project and each team member will be designated a specific role. Each group will produce a prototype and test its sled at the end of the week.

Procedure

Background

During the Swiss Alps emergency sled design chalenge, students learn about the following physics concepts: friction, Newton’s first and second laws of motion, and speed. They gain knowledge about how friction affects the motion of an object. The more friction that exists, the harder it is for the object to travel. The less friction that exists between the object and the surface it is sliding on, the easier it is for the object to travel. Friction is also affected by the mass of the object; on the same surface, a heavy object does not move as easily as a light object.

Newton’s first law of motion states that an object at rest stays at rest unless acted upon by an outside force. Without an outside force, a sled at rest stays at rest. Newton’s second law of motion explains the relationship between force, mass, and acceleration (F = ma). The more force that is added to an object, the larger the acceleration of the object. A more massive object is harder to accelerate.

Finally, the speed of the object is the distance the object travels divided by the time it takes that object to travel a specific distance (speed = distance x time). The shorter time it takes an object to cover a specific distance, the faster the speed of the object.

The force of gravity acts on the object moving down the hill; gravity pulls the sled down the hill after an initial push is made to get the sled moving. When the force due to gravity is greater than the force of friction, the sled moves down the hill. If friction is greater, the sled slows down and stops.

Before the Activity

• Make copies of:
• Appendix G: Technical Report Template (one per group per day)
• Appendix K: Materials List (one per class)
• Day 1:
• Gather materials, place them in a central location in the room so that students can see them.
• Make copies of:
• Appendix A: Pre/Post Quiz (one per student)
• Appendix B: Description of Engineering Design Challenge (one per class)
• Appendix C: Student Performance Rubric (one per group)

• Day 2: Make copies of:
• Appendix E: Speed Calculation Worksheet (one per student)
• Appendix F: Differentiated Speed Calculation Worksheet (one per student, as needed)
• Day 3:
• Ensure ample space for a testing area, such as an empty hallway or side of the room. Set up the testing area according to the testing parameters decided upon during Day 2.
• Make copies of: Appendix D: Engineering Prototype Brainstorming Design (one per group)
• Days 4-5:
• Make copies of:
• Appendix H: Engineering Log (one per group)
• Appendix J: Final Technical Report (one per group)

Day 1: Pre-Assessment, Team Forming and Challenge Kickoff

1. Administer the pre-activity assessment, Appendix A: Pre/Post-Quiz. Use the data for future instruction with speed/graphing.
2. Present the engineering design challenge, as provided in the Introduction/Motivation section and Appendix B: Description of Engineering Design Challenge.
3. Explain that they will be using the engineering design process (EDP) for this project. The EDP is series of steps that guides engineering teams as we solve problems. The design process is iterative, meaning that we repeat the steps as many times as needed, making improvements along the way as we learn from failure and uncover new design possibilities to arrive at great solutions.

   

4. Divide the class into groups of four students each. Assign team members to one of the four roles; project manager, logistics, statistician, and project mediator. 

• Project Manager: Responsible for keeping the team on task and ensuring the group completes the daily engineering report (via Google docs). 
• Logistics:  Responsible for obtaining supplies within the room. 
• Statistician: Responsible for recording data in the engineering log and sharing the results with all team members. 
• Project Mediator: Responsible for resolving any problems that arise. Expected to resolve problems via communication and collaboration among group members. (This job only for groups of four students.)
• (optional) Groupings can be used as differentiation between student groups. 

5. Give teams the following materials: recyclables, water bottle, foil, plastic wrap, cotton balls, Popsicle sticks, and plastic disposable cups. Indicate whether it is permissible for students to bring in additional materials for their sleds.
6. Hand out and read to students the Appendix C: Student Performance Rubric, which provides a detailed layout for how groups receive full credit for their design challenge projects. 
7. With the students, refer to the testing parameters so they can start to brainstorm (step 2 in the engineering design process) how they want to set up the ramp, the distance the sled will travel, ramp angle, etc., which will be decided upon later, during Day 2. 
8. Distribute copies of the Appendix G: Technical Report Template. Each day, teams fill out this report template to proivde:

• Accomplished tasks 
• Problems encountered during the engineering design process and how they were solved
• Immediate future goals for the following day

Day 2: Speed Calculation and Testing Parameters

1. Hand out the Appendix E: Speed Calculation Worksheet to test students' knowledge of speed. For low-level student/IEP groups, use the Appendix F: Differentiated Speed Calculation Worksheet, which gives them the speed calculation to use.
2. Testing parameters: As a class, students decide the testing standards. When testing the sled speed, the group decides the ramp angle, ramp height, ramp length, and set distance the sled will travel. For the safety test, students decide how much cargo (packing peanuts) each sled is required to carry safely, where the collision occurs, and what to use as the barrier. (alternatives) Give students three different options for each testing parameter and have them choose/vote to come to an agreed-upon decision. OR, just have the teacher provide the testing parameters instead of having the class decide by voting.
3. Distribute copies of Appendix G: Technical Report Template. Each day, teams fill out this report template that lists:

• Accomplished tasks 
• Problems encountered during engineering design process and how they were solved
• Immediate future goals for the following day

Day 3: Brainstorm, Build and Interim Testing

1. Provide students with the Appendix D: Engineering Prototype Brainstorm Design sheet. Remind the students that they will now complete the third, fourth, fifth, and sixth steps in the engineering design process: Imagine possible solutions, plan by selecting a promising solution, create a prototype, and test. 

• Teams design three sled prototypes. They must include detailed labels on each design sketch to show exactly what materials go where on the sled.
• As a group, students select their best brainstormed prototype design, which they move forward to construct. 
• Students begin building their best design. Throughout the process of prototype building, make available the testing center for students to test their prototypes periodically. This enables them to continually reflect and redesign (the seventh step of the engineering design process) throughout the build process. Note that the testing parameters are what students agreed on during Day 2. 

2. Distribute copies of the Appendix G: Technical Report Template. Each day, teams fill out this report template that lists:

• Accomplished tasks
• Problems encountered during engineering design process and how they were solved
• Immediate future goals for the following day

Days 4-5: Final Testing, Data Analysis and Final Reports

1. Teams continue building their designs. On the final build day, conduct final tests during which results/data are recorded. 
2. Testing parameter setup: 

• Ideal testing setup: For the ramp, use a thick poster board with glossy side up. Ideally, teams use recyclables that easily slide on the glossy surface.
• Have students mark the distance where to place the barrier. Then have them record the distance achieved, daata needed for sled speed calculation.
• Have students start a stopwatch/timer once the sled is released from the top of the ramp.
• Students record the distance and time in the table and use this information to calculate the sled speed. 
• Students record the following data in their Appendix H: Engineering Log:
• Sled distance, time, and speed
• Safety Chart, level 1 through 3.

3. After testing, place all groups’ final average speeds on a chart/board so that all other groups can see the results.

• Create a bar graph to display the data for the entire class.
• Y-axis: Sled speed
• X-axis: Group numbers/names

4. Groups members complete the Appendix J: Final Technical Report, which requires the following information:

• List all group member names.
• Explain why your prototype is the best solution for the Swiss Alps emergency sled design challenge
• Summarize the overall tasks accomplished.
• If you were given the opportunity to redesign, what would you change in your prototype design, and why?

Vocabulary/Definitions

acceleration: rate of change of velocity with respect to time.

convert: to change into, over, etc.

distance : a numerical measurement of how far apart objects are.

force: any interaction that, when unopposed, will change the motion of the object.

friction: force that resists the relative motion of solid surfaces, fluid layers, and material elements that slide against each other.

mass: property of a physical body.

natural disaster: a natural event such as a flood, earthquake, or hurricane that causes great damage or loss of life.

prototype: an early sample, model, or release of a product built to test a concept or process.

seismic: related to the study of earthquakes.

speed: the distance an object travels in a given amount of time.

velocity: rate of change of an object’s position with respect to a give point of reference.

Assessment

Pre-Activity Assessment

Pre-Quiz: Have students each complete the Appendix A: Pre/Post-Quiz, which includes five different questions that require them to calculate speed given certain information. The quiz also asks them to plot three different points on a coordinate graph, and analyze a distance vs. time graph to determine which vehicle is moving faster. Review student's answers to see if additional explanation would be helpful on any of the topics.

Activity Embedded Assessment

Brainstorm: Have students use the Appendix D: Engineering Prototype Brainstorm Design, which gives them three different spaces to document different brainstorm ideas for sled prototypes. Engineers often take notes on their ideas because they might come in handy in later redesign stages.

Post-Activity Assessment

Post-Quiz: Have students re-take the Appendix A: Pre/Post-Quiz to assess what they learned from the activity.

Rubric: Use Appendix C: Student Performance Rubric to assess students in the following categories: data collection, group member accountability, technical reports, and design sketch.

Investigating Questions

When you are sledding down a hill, is there such a thing as too much weight? (Possible answers: Yes, because you won’t be able to start moving if you’re too heavy, the static friction could be too large, and the sled might not go down the hill; etc.)

Troubleshooting Tips

• Regularly check on the progress of all groups.
• Have one student on each team be responsible to report its progress/difficulties encountered to the instructor.

Activity Extensions

A great way to enable students to experience the forces of gravity and friction for themselves is to have them slide down some snowy hills on tubes at a ski resort or local park. Ask students: Were some hills easier/harder to slide down? Did you go faster/slower on certain runs? Expect students to observe that the hills where no one slid down before were less slippery than well-worn runs. Why? The snow on the popular hills gets smoothed out, which results in less friction between the tube and the snow.

Activity Scaling

• For lower grades, provide teams with an already-created sled base. Perhaps cut off the top half of a plastic water bottle and have teams add materials to this base.
• For higher grades,
• Emphasize student collaboration, by pairing students into teams according to their class average and give them the opportunity to collaborate to present a simple friction/force experiment to the class for value added credit.
• In addition to completing a final technical report, have students present their technical reports to their peers.

Additional Multimedia Support

Swiss Seismological Service (SED) at ETH Zurich is the federal agency for earthquakes. Its activities are integrated in the federal action plan for earthquake precaution. http://www.seismo.ethz.ch/sed/100/Snapshots/05/index_EN AND http://www.seismo.ethz.ch/knowledge/snapshots/index.html

Copyright

Contributors

Supporting Program

Acknowledgements

This material is based upon work supported by the National Science Foundation under grant no. EEC 1405869—a collaborative Research Experience for Teachers Program titled, “Inspiring Next Generation High-Skilled Workforce in Advanced Manufacturing and Materials,” at the University of Dayton, Central State University and Wright State University in Ohio. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.