Flippy, the Dancing Robot

Building Your Robot

1. Gather all the materials you need to build your dancing robot (see the Materials list). Figure 2 shows the main parts of the robot.

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 2. Some of the materials to build your dancing robot (note: some materials and tools, like scissors and tape, are not shown).

2. Put the batteries in the battery holder as follows, and as shown in Figure 3.
   1. Use a small Phillips head screwdriver to remove the screw that holds the cover on the battery holder.
   2. Press down on the cover and slide it off the battery holder.
   3. Place the batteries into the battery holder. Make sure the "+" symbols on the batteries line up with the "+" symbols inside the battery holder.
   4. Slide the cover back onto the battery holder. It should click into place. You do not need to replace the screw.

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 3. Put the batteries in the battery holder.

3. Press corks onto the motor shafts as follows, and as shown in Figure 4.
   1. Carefully use the Phillips head screwdriver (or another pointy object, like a pen) to poke a hole in one side of the cork.
   2. Find the motor's shaft (the white part sticking out from the side), which is on the opposite side from the motor's wires. Firmly press the motor's shaft into the hole you made in the cork.
   3. Repeat steps 3.a.–3.b. for the second cork and motor.

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 4. Mount the cork to the motor shaft.

4. Use electrical tape or duct tape to tape a popsicle stick to the cork, as shown in Figure 5. One end of the popsicle stick should be flush with the bottom of the cork and motor. Do this for both motors.

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 5. Tape a popsicle stick to the cork.

5. Use double-sided foam tape to tape the motors to the battery holder, as shown in Figure 6.
   1. Cut two pieces of double-sided foam tape and place them on opposite ends of the back side of the battery holder (the side without the power switch).
   2. Firmly press the motors onto the double-sided tape so the corks are suspended from the sides (both left and right), as shown in Figure 6. The motors should be pointing in the same direction.

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 6. Tape the motors to the battery holder.

6. Mount the breadboard on top of the motors, as shown in Figure 7.
   1. Peel the paper backing off the bottom of the breadboard, exposing the sticky adhesive.
   2. Firmly press the adhesive part of the breadboard onto the top of the motors.

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 7. Mount the breadboard to the motors.

Connecting the Circuit

Before you connect your circuit, remember to check out the Science Buddies reference How to Use a Breadboard for Electronics and Circuits to learn more about breadboards. To connect the circuit for your robot, follow these steps:

1. Connect the battery holder to the breadboard, as shown in Figure 8.
   1. Orient the robot so the black and silver parts of the motors are pointing to the left, as shown in Figure 9.
   2. Plug the battery holder's black wire into the upper-right hole of the breadboard (where the first row and the far right column meet).
   3. Plug the battery holder's red wire into the lower-right hole of the breadboard (where the last row and the far right column meet).

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 8. Connect the battery holder's wires to the breadboard.

2. Connect one motor's wires to the breadboard, as shown in Figure 9.
   1. Make sure your battery holder's switch is in the OFF position.
   2. Pick one motor (it does not matter which one).
   3. Plug the motor's black wire into the first row of the breadboard, next to the battery holder's black wire.
   4. Plug the motor's red wire into the last row of the breadboard, next to the battery holder's red wire.

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 9. Connect the first motor's wires to the breadboard.

3. Now it is time to test your first circuit.
   1. Hold your robot carefully in one hand, so your fingers and arm will be out of the way of the popsicle sticks when they spin.
   2. Use your other hand to turn the battery holder's switch to ON. Just one of the motors (the one you connected to the breadboard) should start spinning.
   3. If the motor does not spin, make sure you have the wires firmly pushed into the breadboard, and that they are arranged as shown in Figure 9.
      1. Remember, you need a complete circuit in order for the motors to work. If even one wire is disconnected, the motors will not spin.
      2. If you accidentally pushed a wire into the wrong hole, you can just pull it out and re-insert it into a different hole. This is the nice thing about breadboards; they make it very easy to fix mistakes when you are building a circuit.
   4. If the motor still does not spin, open up your battery pack and double-check to make sure the "+" symbols on the batteries line up with the "+" symbols inside the battery pack.
   5. If the motor still does not spin, try using fresh batteries.
   6. Once the motor is working, turn the battery holder's switch back to the OFF position.
4. Connect the second motor's wires to the breadboard, as shown in Figure 10.
   1. Note: You will plug this motor's wires in "backwards" (compared to how you plugged in the other motor's wires). This will make the motor spin in the opposite direction of the first one, causing the robot to "dance" instead of just rolling in a straight line.
   2. Plug the motor's red wire into the first row of the breadboard (next to the black wires from the battery holder and other motor). From left to right, the wires in the top row of the breadboard should now be red, black, black.
   3. Plug the motor's black wire into the last row of the breadboard (next to the red wires from the battery hold and other motor). From left to right, the wires in the bottom row of the breadboard should now be black, red, red.

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 10. Connect the second motor's wires to the breadboard.

5. Now, test your circuit again.
   1. Carefully hold the robot in one hand and turn the power switch to the ON position.
   2. The motors should spin in opposite directions. If one motor does not spin at all, or the motors spin in the same direction, double-check that your wiring matches what is shown in Figure 10.
6. Congratulations, you just built your first robot! Spend some time admiring your creation, and start thinking about how you might want to decorate it or make it sturdier. Move on to the next section when you have some ideas.

Building a Better Robot

Now you are ready to follow the engineering design process to test and redesign your robot.

1. First, you might want to spice your robot up by adding some decorations like googly eyes, as shown in Figure 11. How you decorate your robot is entirely up to you. You could add stickers, pipe cleaners, use markers to draw on the robot, or do anything else you want; googly eyes are just one idea to help you get started!

Image Credit: Ben Finio, Science Buddies / Science Buddies
Figure 11. Decorated robot with googly eyes.

2. Next, try to figure out how you can test and redesign your robot. Start by turning your robot on and putting it in the middle of an open space on the floor. Watch as the robot dances and tumbles around. Does the robot's "dancing" seem similar to any real-life style of dancing?
   1. Note: your robot might work better on carpet than on a slippery surface like tile or wood. Try the robot on different surfaces if possible.
   2. If you use the robot on a table, be very careful and be ready to catch the robot before it falls off the edge.
3. Keep watching until something breaks on the robot (you may want to set an upper time limit on how long you will wait, for example, 10 minutes; you do not want to sit there and watch your robot all day!). Here are some examples of things that could go wrong:
   1. One of the wires might come loose from the breadboard.
   2. One of the corks could pop off a motor shaft.
   3. The double-sided tape holding the motors to the battery pack might peel off.
   4. Some of your decorations, like the googly eyes in Figure 11, might fall off.
4. If something breaks, turn the robot off and investigate what happened.
   1. Which part(s) broke?
   2. Why do you think they broke or fell off?
   3. Write down your findings in your lab notebook. If you have a camera, use it to take pictures of the broken parts of your robot.
5. You wouldn't want your robot to literally "break a leg" in the middle of a dance performance. What could you do to fix the problem and prevent it from happening again?
   1. For example, what construction materials could you use to make the robot stronger?
   2. What about using more tape or rubber bands to secure parts together?
   3. What about using a hot glue gun or super glue instead of tape? Caution: Adult supervision is required when using super glue or a hot glue gun!
   4. What about bundling the wires together or attaching them flat up against the robot's body, so they are not sticking out and easily able to get caught on things?
   5. Could you build a "case" for the robot's body out of cardboard, that encloses the battery pack, motors, breadboard, and wires; but lets the corks stick out of the sides so they can spin?
   6. Important: One thing to keep in mind is that eventually, you will need to change your robot's batteries. So, you should be careful not to permanently glue the battery pack shut or design a case that cannot be opened again to access the battery pack. Make sure you can still slide the top and bottom halves of the battery pack apart so you can change the batteries.
   7. Write down some of your ideas in your lab notebook. If you want, you can also make sketches of your redesigns or changes you want to make.
      1. If you need to keep a formal design notebook for a science fair project, refer to the Science Buddies resource on Engineering Design Notebooks.
6. Now, repair your broken robot using some of the ideas you came up with in step 4. Write down how you repaired the robot in your lab notebook, and remember to take pictures of the repairs if you have a camera.
7. Repeat steps 2–6 until your robot no longer breaks after a certain period of time, and until you are satisfied with your robot's performance. This is a very important part of the engineering design process. Engineers very rarely get something right on the first try!
   1. Remember to document in your lab notebook what breaks and the fixes you make each time.
   2. If you will be entering your project in a science fair, you can use this information and your pictures as part of your report or display board.
8. When you are finally done, enjoy playing with your dancing robot! Have it put on a dance performance for your family and friends!