Part 1: 40 minutes, Part 2: 45 minutes (day 2) 3

The goal is for students to understand the basics of engineering that go into the design of a sneaker. The bottom or sole of a sneaker provides support, cushioning, and traction. In addition the sole is flexible and can have some fashion based functions such as cool colors and added height. The sneaker is a well-engineered product, utilizing a variety of materials to create a highly functional, useful shoe. In this activity, students select specific design requirements, such as good traction or deep cushioning, and then select from a variety of materials to build prototype shoes that meet the design criteria.

Biomedical engineers aid in the design of sneakers. It is not only important for sneakers to look stylish to appeal to the consumer, but to function properly. Different factors must be taken into consideration when designing sneakers, such as who will wear them (male, female, child) and for what type of activity. The user and activity indicates what shoe characteristics are most important for the design, such as traction, height, cushioning, and/or height. engineering design footwear materials science model prototype shoe design sneaker After this activity, students should be able to: Analyze a product's components and function. Recognize a design need or engineering challenge. Develop, sketch and discuss possible solutions and select one. Select appropriate materials for the solution. Construct a working model using a variety of materials. Use, evaluate and suggest ways to improve the product. an assortment of sponges, bubble wrap packing material, foam and rubber, as outlined in Worksheet A (feel free to add or substitute items) twine scissors glue masking tape the attached worksheets (see Attachments section) Sneakers are designed for an assortment of uses. Each use has specific characteristics that must be taken into account before manufacturing the sneaker. People who design and manufacture sneakers want to make sure that they have not overlooked a major new type of sneaker that would appeal to students. Today, you will define specific characteristics for your sneaker, select suitable materials, and build a prototype of what you imagine. A model that is built to test a concept. Resistance to being flexed. Providing a softening effect to forces. Ability to move a load over a surface. The design of today's sneakers is an engineering science that combines physics and biomechanics. The engineering design utilizes materials that provide durability, comfort, cushioning and stability. Good designs also consider the type of foot (female, male, child) since the average shape and structure of each has different characteristics. Typically, a woman's foot is narrower and a higher arch. The inside layout of a well-designed sneaker takes these physical differences into account. Another important component in the design is the consideration of which sport the sneaker will be used to play. Each sport has different footwear requirements. Some need high flexibility, others maximum cushioning or high friction/traction levels. Part 1: Modeling and Building a Sneaker Gather materials for sneaker construction, as identified on Worksheet A: Materials and Properties. Cut out enough fabric bases to provide one for each group, with a few extras in case of mistakes (see Worksheet D: Pattern). As a class, discuss the following: think about the characteristics of your shoes. What would you like to be different about them? What would it take to create a sneaker with that new property or component? What materials do you know about that could be used? Divide the class into groups of 3 or 4 students each and give each group Worksheet B: Design Specifications for the Sneaker to complete. Pass out two copies of Worksheet A: Materials and Properties to each group. Discuss the properties of each material (spring, soft, stiff, sticky, etc.). Pass out two copies of Worksheet C: Materials and Costs to each group. Costs are assigned to each item. The designed pair of sneakers must be within budget, limiting options and forcing engineering trade-off decisions. Distribute two fabric bases plus a bag that includes the materials available for construction of the prototype sneakers. Students can cut or shape materials as desired. If you prefer, set up a "store" at which students can purchase the materials they want by completing and submitting Worksheet C. Once students select the materials that they feel will work best (meet their design criteria) for their prototype sneakers, they should assemble the prototypes using glue and tape. (Students are building two matching sneakers.) Allow the prototypes time to dry. Part 2: Evaluating and Improving the Design Distribute the dry prototypes to the original designers and two lengths of twine for tying on the prototypes. If you have time, have groups present their designs to the class, explaining what worked well and how they would improve their prototypes. Evaluate each design according to the criteria in #3, below. If time is short, enlist the help of another adult to evaluate half of the groups. Test for design success by using the following criteria rated on a scale of 1-3: Height: measure the student's height with and without the sneakers on. Traction: slide around the floor with and without the sneakers on. Cushioning: jump up and down with and without sneakers on. Stiffness: bend and twist prototype sneakers compared to store-bought sneakers. If students suggested any additional design criteria, have the group discuss and decide what would be appropriate tests for design success. Conclude with a class discussion of the following: Compare your sneaker prototypes to some of the sneakers that students are wearing. How do the materials you used compare to the ones in the store-bought sneaker? Are the ideas you've created realistic? What activities are best suited to your design? Worksheet A: Materials and Properties (pdf) Worksheet B: Design Specifications for the Sneaker (pdf) Worksheet C: Materials and Costs (pdf) Worksheet D: Pattern for Cutting Fabric Base Forms (pdf) Use surface coverings to keep glue off the desks and floor when constructing and testing. You may wish to set up a special "test area." These sneakers are only prototypes and should not be used for actual wear after the adult-supervised testing. Which material properties help the sneaker be comfortable when you apply large forces or pressure to your feet? (The greatest comfort comes from materials that are cushioning (soft) and have the ability to "bounce back," or a springiness.) Why is traction important on a sneaker? (Traction is created by friction between the base of the sneaker and the ground. Without traction, shoes slip, as if you were trying to move on an icy surface.) Why do the prices of sneakers vary so much? (Sneaker prices vary because they depend on material costs, marketing costs, manufacturing costs, and supply and demand pressures.) Observe class participation in discussion on sneaker characteristics. Evaluate design success during testing. Rate each criteria on a scale of 1-3. Have students write-up descriptions of their sneaker designs, explaining the reason for each feature that is included and what activities it would be best suited for. Have students create a list of other types footwear. From this list either discuss the importance of (or create a graph that shows) the same design criteria (height, stiffness, cushioning, traction) for each of these. For upper grades, assign students to research the specific materials and combination of materiails that are used to make real sneakers "Sneakers: From Start to Finish (Made in the USA)" Samuel G. Woods, Gale Zucker (photographer)