Engineering Information Transfer

In this lesson, students figure out the phenomena involved in analog to digital conversion by exploring how different technologies use patterns to transfer information from one place to another. They begin with an investigation into how patterns of 1s and 0s can be used to transfer information about a picture. They then apply their knowledge to design and test multiple solutions that use light and sound to transfer information over a distance. 

• Many signals (actions used to communicate information) use patterns to transfer information from one place to another.  
• Patterns are things that happen in a regular and repeated way, and there are different ways to use patterns to send information over a distance.
• There are different systems for communicating messages over a distance, and most of these systems involve the information being coded in some way. A code is a message communicated with a pattern of information (symbols, letters, words, sound, light, etc.)
• Both light and sound are commonly used in more high-tech forms of communication. In a high-tech device such as a cell phone, the information is encoded before it is transmitted.  
• Digital signals are useful because they are a reliable way to send information. They can carry more information than non-digital signals.
• A digital code is made up of numbers, often 1s and 0s.
  
  
  

• How have you experienced sound being used to send information from one place to another?
• Why can light be more useful than sound for sending messages over a distance?
• How can light be used to send a coded message?
• When might using sound be a more effective way of sending a message than using light?
• When you speak into a cell phone, how does your message change before it is transmitted (passed from one place or person to another)?
• What has to happen before the person you’re talking to receives your message?  
• Why is it important that the information be decoded by the other person’s cell phone?
• Why is it useful for information to be coded in a digital format?  
• How can light patterns be converted to a digital code?  
  
  

Misconception: Once someone sends a message in one form, it cannot be changed into another form without changing the meaning of the message.

Fact: Many technologies convert information patterns from one form to another so the information can be transmitted more easily and securely.

Misconception: Sound is always the easiest way to communicate.

Fact: Sometimes sound is the most effective way to communicate, but there are times when it is less effective. It is important to evaluate the situation to determine the benefits and drawbacks of any form of communication.

Code:  a message communicated by a pattern of information (symbols, letters, words, sound, light, etc.)

Communicate:  to share information with

Decode:  to turn coded information back into a form that can be understood

Digital:  technology that translates information into a countable set of numbers, most often ones and zeroes

Encode: to turn information into a format or code so it can be easily and/or securely transmitted

Light:  a form of kinetic energy that travels through space 

Reflect:  to bounce off of the surface of an object

Signal:  an action used to communicate information

Transmit:  to pass on from one place or person to another

Sailing Around the World

When Abby Sunderland was 16 years old, she tried to set a record. She wanted to be the youngest person to sail alone around the world.

Abby began her journey on January 23, 2010. Her boat was named Wild Eyes. She began in Marina del Rey, California. In March, she became the youngest solo sailor to round Cape Horn. Cape Horn is the southernmost point of South Africa.

Sending a Distress Signal

On the morning of June 10, 2010, Abby ran into trouble. There was a major storm. It produced 9- meter (30-foot) waves that damaged her boat. Abby was more than 3,218 kilometers (2,000 miles) from shore. She was in a remote part of the southern Indian Ocean.

All of Abby’s regular ways of communicating were damaged. To communicate means to share information with. She couldn’t use a radio or phone to let anyone know she needed help. At that point, Abby turned to her emergency beacons. The beacons communicated Abby’s location in the ocean. As a result, a search-and- rescue team was able to find Abby’s boat and rescue her.

Signals Transfer Information

Beacons work by sending distress signals. A signal is an action used to communicate information. There are many kinds of signals. If you wave your hands in the air to get someone’s attention, you are sending a signal.

Many signals use patterns to transfer information from one place to another. Remember that patterns are things that happen in a regular and repeated way. For example, if you send three of any signal, it means you need help. This could be blowing three short times into a whistle. Or it could be turning a flashlight on and off quickly three times.

Three whistle sounds or three flashes of light are codes. A code is a message communicated with a pattern of information (symbols, letters, words, sound, light, etc.).

Morse Code

People use different systems for communicating messages over a distance. One of the longest-lasting systems is Morse code. Morse code is a way of encoding text into a series of dots and dashes.

To encode means to turn information into a format or code so it can be easily and/or securely transmitted. To transmit means to pass on from one place or person to another. For example, with Morse code, each letter of the alphabet and number is represented by a sequence of dots and dashes. The dots and dashes can be transmitted by pulses of light, on-off tones, or clicks of sound.

When another person receives the code, they have to decode the message. To decode means to turn coded information back into a form that can be understood.

Morse code isn’t used as often as it once was. However, it is still used in some situations. SOS remains the most common distress signal. It is recognized around the world. SOS is represented by three dots, three dashes, and three dots.

Air traffic control towers use signal lamps that use Morse code. These signal lamps are a backup. They are there in case a plane’s radio stops working.

Sailors in the Navy also sometimes use signal lamps to communicate in Morse code. This is especially useful when there is a need to be silent.

This lesson has two parts, an investigation and an engineering challenge. In the investigation, students use a model to figure out how different kinds of information can be conveyed with phenomena like patterns of light and how the patterns of light can be digitized with ones and zeroes. In the engineering challenge, students use information from a scenario to help them define the main problem facing electrical engineers, who need to transfer information to display a pattern forming a specific image. In the engineering challenge, students work in teams to come up with two solutions, one that uses light patterns and one that uses sound patterns to solve the problem. Once they have built their two prototypes, they test each prototype to determine which prototype was more effective at meeting the criteria of the problem within the constraints. Students use their investigation results and experience in the engineering challenge to communicate about how people can use different patterns to communicate information.