How to assemble your robot
Video coming soon!
- read all the instructions once before you bend, attach, or open anything.
- your kit!
- some masking tape
- some black electrical tape (the line that will be followed)
- A USB "A to B" cable
- Your computer
- 2x bag with a servo and some attachments
- 1x clear plastic box with wires
- 1x blue and white box containing an Arduino board
- 1x breadboard (white with lots of little holes)
- 2x 10k resistors. Click the link for a close up picture.
- 2x photo resistors. Click the link for a close up picture.
The photo resistors are the robot's eyes. Power goes in one side and, depending on how much light they "see", more or less power comes out the other side. By measuring how much we can tell if the eye is in front of a dark something (line) or light something (floor). If you want, you can read more about making a basic photo resistor circuit.
Gently bend the wires of the resistors until they point the same way. Pushing near the fat part will get better results than pulling from the end of the wires.
Break the tape holding the box of wires closed. Add the wires and resistors to the breadboard to match the picture above. The holes are tight so push firmly to make sure the wires are in and there is a good connection. 5 volts will come from the Arduino and flow through the photo resistor. Some will go through the 10k resistor, and some will flow back to A0 and A1 on the Arduino. This is how the eyes work.
Press on the bottom edge of the photo resistors to fold them towards the edge of the breadboard, then bend them down a little so they will look right at the ground. Use the same method to bend the 10k resistors down the other direction so they lie flat on the breadboard.
To power the eyes we need a complete circuit. That means wires have to make a loop.
Add a long wire from the 5V pin on the Arduino to the bottom line of holes on the breadboard. Add another long wire from either GND pin on the Arduino to the top line of holes on the breadboard. Breadboard holes are connected together like this. This means 5V will flow through each photoresistor, then into the 10k, then back to the GND pin. A complete circuit!
Add two more wires as in the picture above. Connect the bottom wire to A0. Connect the top wire to A1.
The drive shaft is the motor source that will push the robot forward, back, left, and right. This is built with continuous servos. These are not quite the same as the servos in RC cars and planes.
Take a servo out of the bag and unwind the wire. Notice the orange/red/brown color of the wires. This will be important later. Do the same for the other servo. Notice the white part that sticks out with the gear teeth? That's the shaft.
Tape the servos together. Make sure they are lined up neatly and don't be shy with the tape. I wrapped mine 5 or 6 times.
Look at the brown/red/orange wire from the servo. Notice the connector on the end? The holes line up with the wire colors.
Take a short wire and attach it to the top (GND) line of the breadboard, then attach the other end to the brown hole of a servo. Do the same for the other servo.
Take a long wire and attach it to the bottom (5V) line of the breadboard, then attach the other end to the red hole of a servo. Do the same for the other servo.
Take a medium wire and attach it to pin 2 of the Arduino. Pin 2 is on the far side of the board from A2. Connect the other end to the orange hole of a servo. Do the same for the other servo but connect it to digital pin 4.
The servo attached to digital pin 2 will be the left wheel. The servos will go under the back end of the breadboard, with the servo shafts as far from the photoresistors as possible. The servos can be taped in place. You're going to need the motor shafts soon, so don't block those with tape.
If the end caps from the CanDo container are not round, you can use the bottom of coffee cups. The first version I built used large cups from a fast food restaurant. The wheel will have a hollow side, like a bowl. Lay it on a table so the bowl is upside down.
The servos came with a small bag of wheels and "horns". One of the horns is star shaped. Tape the star into the center of the wheel and then attach the wheel to the servo shaft. Do the same for the other servo and wheel.
After you have programmed the robot you can attach the 9V battery to the Arduino to run it without a wire.
Let's go program your robot...