Happy Holidays!

The Little Tinkerer will be on break until January. We hope you enjoy the holidays, and here are some cool engineering videos to check out while you wait!

Engineering at NASA 

3D printing!

https://www.youtube.com/watch?v=Llgko_GpXbI

LEGO robots

Make Your Own Balloon Hovercraft

Materials:

• Blank CD or CD you don't want any more.
• Pop-top cap from a water bottle or dish soap bottle
• Balloon
• Glue

Procedure:

1) Glue the pop up lid firmly onto the CD directly over the hole in the CD and let the glue dry.

2) Push the pop-top cap closed. Blow up the balloon, then hold it so that no air escapes, but don't tie it off. Stretch the mouth of the balloon over the bottle cap
3) Place it on a flat surface and let it go.

What Happened:

Air from inside the balloon escapes through the hole in the pop up top and flows out and under the CD. The CD has a flat surface with an even weight. So the airflow flow from the balloon creates a thin layer of air between the surface of the floor and the bottom of the CD. This reduces the amount of friction between the CD and floor and the hovercraft easily floats and glides on the pocket of air. This is the same way in which a hockey puck table game works! You can make up all sorts of games!

For more information go to: http://www.sciencebuddies.org/science-fair-projects/project_ideas/Aero_p033.shtml

Scratch- Coding for Kids Episode II!

If you had fun with our post about Hopscotch, want to learn how to code, or even just think video games are cool, you should check out Scratch!

Scratch is an online tool where you can learn the basics of coding. Just like in Hopscotch, you can drag little blocks of code around to make cool things happen.
But you can access Scratch from any computer (windows, mac, or linux) that has internet!

This is what the code editor looks like in Scratch

You can look at different types of starter projects here. There are loads of cool examples, like video games, interactive art, a virtual tour of an office at MIT, and even games that sense your motions (they use your webcam) and let you control the game by moving!

This is Society of Women Engineers member playing this video game. You use your hand motions to bounce legos up and save them from drowning! The game uses your webcam to detect your hand motions.

When you're ready to try Scratch out yourself, go to the code editor. On that page, there's a really great "getting started" section on the right that will help you get used to using Scratch.

Happy coding!

Exploring Mars

The Curiosity Rover has been on Mars for about two years, collecting information so that scientists here on Earth can figure out whether or not Mars ever could or ever did support microbial life. The rover has a mass of about 900 kg and is about as big as a car. Ever wonder how something that big and that heavy landed on the surface of Mars?  A group of very smart and talented engineers and scientists developed the technology to make this possible. Watch this video to learn more about the landing sequence.

            What makes Curiosity special is that it can not only take pictures of the surface and acquire information about things like the weather on Mars; Curiosity is able to drill and scoop up the contents of rocks and soil, deliver a small sample to instruments inside the rover, find out what elements the sample is made of, and send all of that information back to the scientists on earth.

           

 A few more fun facts about Curiosity:

1.     It has 17 cameras on board. Some were used to help the rover land on the surface, some are used to take pictures so that the rover and people down here can know where it’s located, and some are used to take selfies! 

This selfie was taken by the Mars Hand Lens Imager (MAHLI).

2.     Engineers can drive the rover themselves by telling it exactly where to go and how to get there OR they can tell the rover where they want it to go and the rover figures out its own safe path to its destination.

3.     The holes in the wheels are particularly interesting. They let the dirt out if it gets trapped inside the wheel, BUT they also spell out the letters J-P-L in Morse Code! JPL stands for Jet Propulsion Laboratory, the NASA center that developed Curiosity. So now everywhere the rover goes, it leaves these markings that spell JPL all over Mars!

4.     One of the ways Curiosity can analyze rocks and soil by “zapping” them with a laser! The instrument that does this, ChemCam, is located where you see the big circle on Curiosity’s “head.”

From landing Curiosity to how it’s being operated until today, exploration of this world outside of our own is made possible by engineers and not just aerospace engineers. A project as big as this needs mechanical engineers, electrical engineers, and computer scientists as well. To date, Curiosity has been making some amazing discoveries. To find out more and stay up to date on the mission, visit the mission's page at http://mars.jpl.nasa.gov/msl/  or check out Curiosity’s Twitter account! 

Engineering in the World of Sports!

Do you play sports? Vijay Gupta, a UCLA engineering professor, has been researching ways to make football helmets safer to prevent concussions. Gupta is testing an additional layer of flexible polymer* that lessens the force of helmet-to-helmet hits and to protect the human head and brain. Adding 5 millimeters of polymer to one’s helmet can reduce force by up to 25%. Aside from football, adding this extra layer to runners’ sock lining could preserve knee cartilage for an additional ten to fifteen years. Gupta uses lasers and a hammering machine the size of a grandfather clock to test this new material. The research Gupta and his students do could also work in military helmets, preventing brain injuries on the battlefield. So as you can see, this mixture of mechanical, materials, and bioengineering has applications everywhere, from the research lab to the football field and beyond!

*polymer: a chemical compound formed from long chains of the same molecule group (example: plastics)

Read more about Professor Gupta's work here:

http://www.mae.ucla.edu/news/news-archive/2013/vijay-gupta-making-football-helmets-safer-to-prevent-concussions

Make Your Own Ice Cream

Did you know that you could turn milk (plus a few other ingredients) into ice cream because of the amazing abilities of sodium chloride, also known as salt? Sodium chloride lowers water’s freezing point.  So how can you use this property to make your own ice cream?  I’ll explain after we go over the materials and procedure for this delicious experiment!

What you will need:

½ cup milk

½ cup heavy cream

¼ cup of sugar

¼ teaspoon of vanilla extract

½ cup of salt

2 cups of ice

1-quart baggie

1-gallon baggie

Thermometer

Measuring cups

Spoons

Procedure:

Add all ingredients except ice and salt into the quart size baggie.

Put the ice into the gallon size baggie.

Record the temperature in the gallon size baggie using the thermometer.

Add ½ cup of salt to the gallon size baggie.

Place the sealed quart size bag into the gallon baggie and seal.

Shake the bag holding it at the edge for about 10 minutes.

Open the bag, and measure the temperature inside the gallon size bag, and enjoy your homemade treat!

  

When you measured the temperature for the second time, the time when there was salt, did you notice how much colder it was than your initial reading? Did you notice the ice melted? This is because salt lowers the freezing point of water. The ice also absorbed energy from the ingredients and from the shaking so it changed states from a solid to a liquid.  So why did this make the milk turn into ice cream?  Well as the milk got colder from its surroundings getting colder, it expanded.  The molecules slowed down and froze making you ice cream!

Foam Marble Roller Coaster

Do you love roller coasters?! 
Now you can create your own with: 

The Foam Marble Roller Coaster!

Materials: 1-3 marbles, foam pipe insulation, duct tape, cups (optional, to catch marbles)

Procedure: This project is all about experimenting!

1: Separate the foam pipe insulation into two pieces length wise as seen in this picture:

2. To make your roller coaster longer, tape the ends of two lengths of the pipe using duct tape and try to make the transition as smooth as possible. Also, use the tape for enforcing the structure of the coaster throughout.

3. Now it’s your turn to do whatever you want! Experiment with the pipes. See what ways you can shape them to create the coolest, fastest, roller coaster. Have a competition with your friends to see who can build the coolest one!

The Science Behind It!

Every kid knows that if you put a marble at the bottom of the roller coaster it isn't possible for it to go up. This intuition is backed up by science.

When an object has height, it possesses something called potential energy. Potential energy is represented by the mass times gravity times the height of the object (mgh). 

When the marble is let go from the top of the roller coaster, it converts its potential energy into kinetic energy. Kinetic energy is the energy released when the object is moving. Kinetic energy is represented by the one half times mass times velocity squared (1/2m(v^2). 

You can use this information, for example, when you are creating loops along your roller coaster! For the marble to have enough kinetic energy to go through the loop, it must first start off with enough potential energy, or enough height. 

For more information, visit: http://www.sciencebuddies.org/science-fair-projects/project_ideas/Phys_p037.shtml#procedure

Hopscotch - Coding for Kids

Ever wondered how everyone's favorite mobile games are program? Hopscotch, a mobile app of its own, is designed to teach you the fundamentals of computer programming through fun games and activities. 

Hopscotch is offered on the iPad for FREE. In the app, you can create games, stories, animations, and apps all by dragging and dropping blocks of code . 

The app is fully interactive and open ended. You can code in different events on the iPad, such as shaking it or using the mic to track loud noises. Hopscotch can be used to build anything and the only limit is your imagination.

Check out Hopscotch's website here.

How do you build a circuit?

A basic component of electrical engineering is a circuit. A circuit is simply a loop that has a current running through it. The current helps the circuit do whatever it was designed to do, like send information from one source to another or power an object, like a LED light. So, how do you build a circuit?

It's actually pretty simple. All you need is a power source and connections. See, most power sources, like a battery, have two terminals: a positive one and a negative one. Current is created when there is a path from one terminal to the other. This path can be created using wires. Whatever is put in the circuit will also get the current, helping it do whatever it needs to do.

Most of the times, engineers like to test out their circuits before they finish them. This is when a breadboard is used. The breadboard has holes on the top so that you can use wires to connect the things in your circuit together. Each column of the breadboard has a wire underneath it to make checking your circuit easier. You make your circuit on the breadboard and check to see if it works right! 

Once you're sure your circuit does what you want it to, you finish it by fixing it to a circuit board. A circuit board is made out of copper and is printed with your wire connections on it. You can design it so that it works for your circuit. Once you get your circuit board, you just need to attach your elements to it, and you have a fully finished circuit, like the one below!

These days, there are new inventions to make this process simpler. One cool new thing is the Circuit Scribe. It has ink that has the same qualities as wires do, so the ink can carry current through them. Now, we can just use paper to make our circuits on instead of breadboard and circuit boards. Check out www.kickstarter.com/projects/electroninks/circuit-scribe-draw-circuits-instantly to learn more!

Bake the perfect cookie!

Have a bake sale coming up? Or maybe a sweet tooth that won't quit? Then we have got the experiment for you!

Make your own Rubber Band car!

How can you make a car with just things around your house? Read on to find out!

The Experiment

Materials:

• 2 paper or plastic cups with lids
• Scissors
• Duct tape
• Stick
• 3-4 rubber bands
• 1 paperclip
• beads with big holes
• Pen or pencil

Try it out:

1. Cut out a small hole on the bottom of each cup. Make sure that the holes line up when you put the bottoms of both cups together.
2. Tape the bottom of both cups together.
3. Poke holes in the center of the lids of both cups. 
4. Connect the rubber bands together by looping them into each other, making a chain. You can do this by putting one rubber band half way through the other, and tucking one end through the center, like this: 
   
5. Thread the rubber band chain through the one lid, the hole in the bottom of the cups and the other lid.
6. Loop a paper clip through one end of the rubber band chain to stop it from going into the cup. 
7. On the other end, put a bead in the rubber band, and then put the stick through the remaining end of the rubber band loop. Your finished car should look something like this:
   
8. Twist up the rubber band and let the car go! 

What's happening

When the rubber band is twisted, it is storing potential energy. Potential energy is energy that is stored in an object. When the rubber band is released, this energy gets turned into mechanical energy. Mechanical energy is energy that does work. 

The only place this energy can be let out is in the paper cups, causing the paper cups to turn, making your car move forward. 

If you thought this was cool...

This project is related to mechanical engineering. You can find out more here. Some concepts used in this project are potential and mechanical energy. You can find out more about energy through this project.