Ingenuity – The Mars Helicopter

Mars Helicopter

Did you know that NASA has landed a helicopter on the surface of Mars, and it is getting ready to be the first device to fly in the atmosphere of another planet?  The Perseverance mission to Mars of this year carried the small test helicopter to see if flight is a good way to study distant planets and moons in our solar system.  The helicopter called Ingenuity is rather small and very light. It stands only 19 inches tall and weighs only four pounds! The main body is only about as big as a softball.  It was designed to fly on its own path using its sensors and artificial intelligence.  Mars is too far from Earth to directly pilot the craft as it takes about 10 minutes to get a radio signal to reach Mars.  It has to overcome some big engineering challenges.  First, helicopters use spinning blades (sort of shaped like wings) to provide the lift necessary to allow flight. That is much easier on Earth with a rather thick atmosphere, it is not so easy to fly in Mar’s very thin atmosphere.  Secondly it can get really cold on Mars, like -130 degrees F at night!  Ingenuity needs to keep its batteries, camera and computers warm with heaters and insulation.  That all adds weight and makes it necessary for the blades to spin fast enough to provide lift.  In this lesson you will learn about the first flight of Ingenuity, the thought that went into the design, and about the importance of coding.

ENGAGE

In this ENGAGE section you will view a short video that highlights Ingenuity’s capabilities and mission.* You can view the video by clicking the link below or by clicking the image to the right.

Question:  In what way is Ingenuity similar to toy helicopters or toy drones you may have played with?  How is it uniquely different?

EXPLORE

In this EXPLORE section you will make a model of the Mars helicopter Ingenuity using easily obtained materials.

Materials:

  • One large marshmallow
  • Four small marshmallows
  • Five toothpicks
  • Construction paper or cardstock (to either trace or print off blades)
  • Scissors

EXPLORE

In this EXPLORE section you will make a model of the Mars helicopter Ingenuity using easily obtained materials.

Materials:

  • One large marshmallow
  • Four small marshmallows
  • Five toothpicks
  • Construction paper or cardstock (to either trace or print off blades)
  • Scissors
Helicopter

Steps

The large marshmallow represents Ingenuity’s main body or fuselage.  This is where Ingenuity stores its batteries, heaters, computer, camera and motor.  Insert four toothpicks as shown to form Ingenuity’s legs. The legs are designed to support the helicopter on the Martian surface even though they are very light weight. The real legs actually fold up. Your model should look like the construction in Figure 1.

Place a small marshmallow at the end of each of the four toothpicks as shown in Figure 2. They represent the round landing pads just like the ones found on Ingenuity. They allow the copter to sit firmly even on somewhat uneven Martian surfaces.

helicopter propeller

Next you can either print out the template of the rotor blades and solar panel on cardstock or you may print them on regular paper and glue them to construction paper.  Then cut out the set of parts for the next step. You should have three items like in Figure 3.

Next make a small hole (see Figure 4) in the middle of each of the parts you cut from the template. You can use a pencil point or push pin. This will allow the paper items to slide over the last toothpick. Be careful with sharp objects. You may wish to have an adult help you.

propeller

Now push a toothpick through the hole in the center of one of the rotor blades of the helicopter. The rotor blade should be about ¾ of an inch from the end of the toothpick like in Figure 5. On the real helicopter, the blades are about 4 feet long and spin super fast (about 2800 revolutions per minute). The blades are stiff and large and rotate so quickly to create enough lift- the upward force of the copter – in this very thin Martian air.

Mars

Now put the toothpick through the hole of the second rotor blade and adjust the blade so that they are aligned in different directions as seen in Figure 6.  They should be slightly separated. Ingenuity has two rotor blades to create enough lift. Also the two blades rotate or spin in the opposite direction.  Helicopters with only one set of blades usually needs a tail rotor to stop the body from rotating in the opposite direction. By rotating in the opposite direction, the forces created by the two rotor blades cancel each other out. A lot of toy helicopters use this trick.

propellers

Next push the end of the toothpick with the rotor blades through the hole at the center of the solar panel as in Figure 7.  There should be about ¼ and inch of the toothpick sticking out from the top of the solar panel. This represents the antenna located atop IngenuityQuestion: What do you think the antennae is used for?

On ingenuity, the solar panel converts the Sun’s energy into electricity to charge the batteries.

Finally push the end of the toothpick which is furthest from the solar panel down through the center of the top of the large marshmallow as shown in Figure 8.

Optional:

Put your helicopter on Mars!  Click the link below to download a NASA image taken from a Mars rover. Display your completed model on that picture.

https://www.nasa.gov/mission_pages/mars/images/index.html

Digging Deeper

The main mission for this little helicopter is to demonstrate that flight is possible on distant worlds such as Mars. It has been deployed on the surface by the Perseverance rover.  As of April 2021 a brief test of the rotor blades has already happened.  A series of short flights, each lasting about 90 seconds or so and reaching a maximum altitude of about 15 are planned.

Since Mars lacks a magnetic field, compasses cannot be used for navigation.  QuestionWhat do you think

Hopefully, Ingenuity will pave the way for future missions involving flight. Flying rovers can study areas of the Martian surface that cannot be reached by ground based rovers.  Question:  Do you think a flying rover like Ingenuity would be useful for a study of the Moon?

EXPLAIN

In this EXPLAIN section you will use everyday materials to investigate the way rotor blades are used by Ingenuity to provide lift. You will be using NASA engineering processes to construct your own flying helicopter and modify it to alter its performance.

 The process for the activity can be found here:

 https://www.jpl.nasa.gov/edu/learn/project/make-a-paper-mars-helicopter/

An instructional video can be found here:

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

Materials:

  • Plain paper OR a copy of the template (downloaded from NASA link above)
  • Scissors
  • Measuring tape
  • Pencil
  • Optional: 3 meter length of light ribbon or smartphone camera

Cut out the helicopter. Use the template or make your own version. Cut along the dashed lines of the template. If you are using plain paper, make a sketch of the helicopter solid and dashed lines as a guide.

Steps

Fold the helicopter along the solid lines. The propeller blades, A and B should be folded in opposite directions along the solid lines.  The X and Y panels fold toward the center and Z is folded upward to give the body of the helicopter rigidity and lower its center of gravity for more stable flight.

Do a test flight. Stand up and hold the helicopter by its body. Raise it as high in the air as you can.  Now, drop it.  What do you observe?  Which way doe the blades turn?   Drop the helicopter from a higher spot. (You can climb a few stairs or stand on a step stool.)  How does the performance change?

Compare the helicopter with a piece of paper. Grab an unfolded piece of paper the same size as the one used to make the helicopter. Drop it at the same time as the helicopter.  Which falls faster? Now wad up the piece of paper into a ball.  Drop the paper ball at the same time as the helicopter. Which falls faster? Can you guess why?  (Hint it has something to do with air resistance.)

Experiment. Make one change to your helicopter. Try folding the bottom up one more fold, or shortening the shape of the blades.  How does the performance of your helicopter change?  Why? Can you figure out a way to make your helicopter blades turn faster or slower?

Revise your model. Engineers often have to build various prototypes to see which design performs the best.  Because Mars has a very thin atmosphere, NASA engineers had to build two sets of enormous blades that rotate 10 time faster than the helicopter blades on Earth.  Think about how you would want to improve the performance of your helicopter and make another one that is different from your first.  Maybe use a different kind of paper or make a much smaller one, or a much larger one.  How big a helicopter can you make that still works? How do helicopters with different blade sizes compare in performance?  What size works best?  How do you define “best performance”?

Reverse it. Notice which way your helicopter blades turn. Is it clockwise or counterclockwise?  Is this consistent for all of your helicopter designs?  What is a single change you can make to your helicopters to make them spin in the opposite direction?

Count the rotations. Measure the height of your shoulders and write this down. Choose your best working helicopter and drop it from shoulder height.  Count the number of rotations it makes before landing. It may be difficult to count the rotations because of the speed. You can record the drop on your smartphone (maybe use “slow motion” if your camera allows).  You may attach a thin piece of ribbon to the bottom of our helicopter body.  You can count the twists in the ribbon after it lands.  Record this number next to the drop height.

A good deal of confidence in your experiments comes from doing multiple trials of the experiment.  Repeat the experiment from a lower height and record the data.

How many times would your helicopter rotate if you dropped it from a taller height? Measure a taller height, and then predict the number of rotations your helicopter will make.

Test your prediction. Drop your helicopter from the taller height and see how close your prediction was. Try from other heights and see if you can make a better prediction each time.

EXTEND

In this EXTEND activity, you will have the opportunity to design and build your own Mars helicopter game using a free program called Scratch.  Scratch is a visual programming language.  In this game you will learn now to load up a Mars background, add a Mars helicopter sprite/icon and program the game to challenge your friends and family.  You will most likely wish to start your own free Scratch account to save your game, edit old games and find links to start or play new games.  Follow the links to get your own free Scratch account.

https://scratch.mit.edu/

Go to the Jet Propulsion Laboratory page below.  There you will find directions, video instructions and hints on how to make your game. A print version of the instructions are found in the text below the link.

 https://www.jpl.nasa.gov/edu/learn/project/code-a-mars-helicopter-video-game/

Materials

Steps

Get set up

  1. Download the Mars surface images and the Mars helicopter sprite image, and save them to a computer. Unzip the surface images zip file into a new folder. There are jpg and png versions of each file.
  2. On the Scratch website, click Create to begin a new project. (Sign in or create an account, if you want to save your work so you can revisit or redesign your game in the future.)
  3. Create a new backdrop by moving the mouse over the Choose a Backdrop icon in the Stage window and selecting Upload Backdrop. Pick the Mars surface image of your choice. The Stage area of the screen should now display your selected backdrop image. Click for an example (image).
  4. Create a new sprite by moving the mouse over Choose a sprite in the Sprite window and selecting Upload Sprite. Choose the helicopter sprite image. There should now be a helicopter placed over your backdrop image along with the original cat sprite. Click for example (image).
  5. Delete the existing cat sprite by clicking on it in the Sprites window and clicking the “x” in the corner.
  6. With the helicopter sprite selected, you’re ready to create the code that manages the game and controls the helicopter!

Make the Helicopter Fly

NASA’s Mars helicopter is a technology demonstration intended to prove that a small, lightweight helicopter can fly in the thin atmosphere of Mars. The helicopter on Mars won’t be controlled with joysticks or keyboards. But in the future, astronauts in orbit around Mars or on the surface of the planet could use remote controls to fly helicopters. Your game can use keys on a keyboard to make the helicopter fly.

Tasks

  1. Make the helicopter fly up, down, left and right on the screen using four different keys on the keyboard. Hint: See if a block in the Control section will help. Click for example (image).
  2. Specify how far the helicopter will move each time one of the keys defined above is pressed. Select a number that makes the helicopter movement appear smooth when the key is pressed and held. Hint: See if a block in the Motion section will help. Click for example (image).
  3. Make the helicopter stay oriented with its rotor on top no matter what direction it is traveling.
  4. Bonus: Create a script that uses sprite costumes to make the helicopter appear to rotate.

 

Add a takeoff location

The Mars helicopter will travel to the Red Planet on the belly of the Perseverance Mars rover. After Perseverance lands, it will place the Mars helicopter in its first takeoff location on the surface of the planet. You can specify a takeoff location for your helicopter by creating scripts that place it at a certain location at the beginning of the game.

 

Tasks

  1. Create code that puts the helicopter in a specific location at the beginning of the game. Make sure it’s starting on the ground, not in the sky!
  2. Bonus: Modify your landing code to make the helicopter start in a random location on the ground.

 

Add a landing site

The Mars helicopter will make up to five flights on Mars starting with a controlled vertical takeoff and landing. Later, its flights will become more complex, reaching heights of 10 to 15 feet and distances up to hundreds of meters.

Tasks

  1. Create a visible landing target on the backdrop image. You can draw a landing location with the backdrop editor, or add a sprite that will serve as a landing target. Avoid putting the landing target over large rocks that could damage the helicopter upon landing. While the real Mars helicopter won’t have a marked landing spot for its flights, your game players will need to know where to land.
  2. Bonus: Generate code that identifies an unmarked region as a safe landing area that game players must find by attempting to land in different regions. Remember, you’ll want to place these unmarked regions in areas without large rocks!

 

Add a countdown timer

NASA’s Mars helicopter will make incrementally longer flights, lasting up to 90 seconds. One constraint that limits the flight time is the amount of power stored in the helicopter’s batteries. You can create a timer that counts down to the end of the flight and ends the game. Your timer should not be so short that the game is unplayable or unwinnable, but it should not be so long that there is no challenge to successfully playing the game. You may need to adjust your timer if you change your helicopter’s speed or the landing site.

Tasks

  1. Create a timer that counts from a set time down to zero. Hint: Create a Time variable that you can program to change. Click for example (image).
  2. Make gameplay stop when the timer reaches zero.
  3. Make a “Mission Over” message appear when the timer reaches zero.
  4. Make the timer start over when a player clicks the green flag to restart the game.
  5. Bonus: Develop code to bring the helicopter down to the ground regardless of where it is when the timer reaches zero.

Indicate mission success!

The Mars helicopter is a technology demonstration mission. It will help NASA prove that a helicopter can fly on Mars, something that has never been done. Mission success for the Mars helicopter will be achieved when it makes its first controlled flight on Mars.

Tasks

  1. Create code that announces a successful mission once the helicopter safely lands on the landing site.
  2. Make gameplay stop when the landing occurs.
  3. Make a script that stops the mission-over script from running when mission success has been achieved.

EVALUATE

In this EVALUATE section, you will have to put what you have learned into focus.  As you have learned the first flight on any other planet than Earth posed a great deal of challenges.  Mars and Earth are quite different.  Use your insights to answer the following questions:

In what ways are the conditions found on Earth and Mars similar?  How are they different?

List four things you know about the Mars helicopter Ingenuity.

Why do you suppose that having missions with flying probes like Ingenuity can study more of their target planet?  How would a rover like Perseverance be limited on where it can study the planet?

For Fun

In the space below you can make a sketch of your own helicopter design.  Why would having a coded program be useful?  What kinds of sensors and cameras would you include?  How would your helicopter differ if it were to be flown by astronauts?  You can design your future helicopter below.

 

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