Soft Landing


  • 1

    Here are some of the materials you can use

    • 20 assorted rubber bands
    • 10 balloons (9-in. [23 cm])
    • 10 craft or popsicle sticks
    • hardboiled eggs (have a few available in case one gets cracked before testing or retesting your device)
    • 1 large paper cup
    • 8 small binder clips (about ¾-in. [2 cm])
    • 2 small paper cups (3-oz. [89 ml])
    • 5 straws
    • string (about 40 in. [102 cm])
    • tape (any kind)
  • 2

    Prepare ahead of time 

    • Have paper and a pencil ready to write down ideas and sketches as you design.
    • Think of cushion (airbag) systems and the things they protect. (Bubble wrap protecting fragile items; airbag protecting driver; spring floors protecting athlete’s joints and muscles)
    • Blow up a balloon and practice attaching a small rubber band around the neck.
    • TIP: You can use a “slip-through” knot to attach the rubber band to the balloon: Wrap the ends of a rubber band around the balloon; slip one end through the loop on the other end; pull tight. You may need an adult to help you practice this tricky step.
  • 3

    Think about the challenge

    • What is a shock absorber? 
    • How many balloons will you need to cushion the egg?
    • What are some reasons to use an airbag cushioned landing? 
    • TIP: Shock absorbers are devices that absorb, or soak up, some of the jolt or energy of an impact. Your body has its own shock absorbers. When you jump off something high, you absorb some of the energy by bending your knees and back. 
    • TIP: Airbag cushioned vehicles can land on a variety of land types or terrains (types of surfaces).
  • 4

    Think of and write down ideas

    • Is the egg more likely to break if you drop it from a few inches or a few feet above the floor? Why? 
    • How will you arrange the airbags on your device so they absorb the shock of the impact?
    • What things other than shock absorbers do you need to think about to help protect the egg? 
    • How will you keep your landing frame from breaking open when it hits the ground?
    • TIP: Due to the increase in speed because of gravity, the egg gains more energy when dropped from a greater height than from a lower height. The greater the energy, the greater the force of impact. 
    • TIP: Airbag landing systems typically have a way to effectively absorb shock, stay intact upon impact, and protect an object on all sides.
  • 5

    Look at the materials 

    • What types of materials will absorb the shock of an impact? 
    • What materials do you have to build the different parts of your airbag system?
    • How will you design a container to hold the egg?
    • How will you keep the egg in the container?
    • How will you attach the balloons to your landing frame?
    • TIP: Soft, springy things, such as balloons, marshmallows, cotton balls, foam, and air-filled packing material, make good shock absorbers.
  • 6

    Design and build the container

    • Decide how you will build the container to hold the egg firmly in place. 
    • Choose your materials and build the container.
    • Place the egg in the container.
    • TIP: The container will need to protect the egg on all sides because you don’t know which side it will land on.
    • TIP: When you drop an egg, it travels faster and faster as it falls towards the floor. The egg stops when it hits the floor. If the force of the floor against the eggshell is too great, it breaks. Soft materials surrounding the egg will help cushion the fall and allow it to stop more slowly. This will take away impact, so the egg doesn’t break.
  • 7

    Design and build the container (continued)

    • Think about how you can protect egg from coming out of the container.
    • Secure the egg in the container.
  • 8

    Design and build the landing frame 

    • Think about what materials you will use to build the landing frame.
    • Decide how you will attach the balloons to the frame.
    • Build the landing frame.
    • Attach it to the container that holds the egg.
    • TIP: The container needs to stay intact, or unbroken, upon impact so the egg doesn’t roll out and break.
  • 9

    Design and attach the shock absorbers

    • Choose the materials you will use for your shock absorbers.
    • Prepare the shock absorbers.
    • Attach them to the landing frame.
    • TIP: If balloons are one of your shock absorbing materials, blow them up and wrap a rubber band around the neck of each one to make it easier to attach to the landing frame.
    • TIP: If a shock absorber breaks, check to see if there are any sharp edges on your frame that need to be covered or adjusted.
    • TIP: Tape is not a very flexible material and it doesn’t stretch. If the tape breaks or scratches the shock absorbers, remove or smooth out any tape sections that have sharp edges.
  • 10

    Test your airbag

    • Hold your airbag system about 3 feet (0.9 m) off the ground. Use the 40-inch (102 cm) string to measure.
    • Release your airbag system and let it fall.
    • TIP: Engineers always review and modify their early ideas. It’s part of the design-build-test process. Testing reveals things about a design and the materials. Engineers use that information to improve a design before going any further.
  • 11

    Check the egg

    • Open the container and check the egg for cracks.
    • Make adjustments to your airbag system if the egg broke. 
    • Then retest it.
    • TIP: If the balloons fall off the landing system, try using different materials (such as string or paper clips) to attach the balloons. 
    • TIP: If the egg comes out of the container, try securing the container with tape or rubber bands so it won’t open up.
  • 12

    Did you know?

    • NASA Explores Space
      NASA engineers have designed and built three rovers that have used an airbag landing system to land safely on Mars. As the rovers approach Mars, they’re going about 12,000 miles (20,000 km) per hour. Thanks to a parachute, heat shield, and rockets, the airbag wrapped rovers hit the surface going about 50 miles (80 km) per hour. One rover bounced as high as a five-story building. Then, after 15 bounces, it stopped rolling, the airbags deflated, and the rover safely landed, allowing the mission to begin. 
  • 13

    Try this next!

    • Modify your landing system. Can you protect the egg as you drop it from 78 inches (198 cm)? Can you go even higher? 
    • Slow down the landing.  Add a parachute or other system to slow the landing system before it hits the ground.
    • Go bowling. Give your landing system a rolling test. Can your system protect the egg as it rolls across the floor?