Robotics Kit 1 - Hardware

Start 

This is the Main Project for this kit. We'll be using the WiFi module to create a web server that will allow us to wirelessly control a robot. We'll use HTML and CSS to format and customize your web server and an I2C motor driver to control the motors.

Modules 

Gather the following parts to complete this project.

Parts

All Parts
All Parts
Robotics Kit Chassis
DC Motor with Gear Box
Tire
I2C Motor Driver
Cables
9v AA Battery Holder
Robot Body Level 1
Motor Mounts
Line Finder Module
Line Finder Mount
Encoder Wheel
Steel Omni Wheel
M3 20mm Standoff
M3 30mm Machine Screw
M3 10mm Machine Screw
M3 Hex Nuts
M3 Nylon Locking Nuts
M2 10mm Machine Screw
M2 Hex Nuts
Sharpie
Screwdriver (phillips and flathead)
PartQuantity
Robotics Kit Chassis 1
DC Motor with Gear Box 2
Tire 2
I2C Motor Driver 1
Cables 3
9v AA Battery Holder 1
Robot Body Level 1 1
Motor Mounts 4
Line Finder Module 2
Line Finder Mount 2
Encoder Wheel 2
Steel Omni Wheel 1
M3 20mm Standoff 2
M3 30mm Machine Screw 4
M3 10mm Machine Screw 6
M3 Hex Nuts 10
M3 Nylon Locking Nuts 6
M2 10mm Machine Screw 10
M2 Hex Nuts 10
Sharpie 1
Screwdriver (phillips and flathead) 1

Note:

In your kit there is a 9v AA battery holder to run the motors with. If you would like your robot to move faster (or you would just like to use a different battery) then you can use any battery between 6 to 15 volts. Do not use any battery greater than 15v or you may damage the motor driver. Do not use any battery lower than 6v because the motors will not have enough power to turn.

Important:

Be sure to follow the instructions below in the order they are given in order to make construction of the robot as easy as possible.

Calibrating Line Finder modules 

First you'll need two line finder modules, two cables, a piece of paper, and a sharpie or a black marker.

  1. Take a cable, unwrap it, and plug one side into one of the line finders and the other into any Digital socket.

  2. Then take your black marker and the sheet of white printing paper. Draw a long thick rectangle. The size doesn't have to be exact but approximately 1/2" wide and 2" long.

Parts Needed
Parts Needed
Line finder modules with cables
Take one end of one of the cables
Plug into one of the line finders
Repeat for other line finder
Plug line finder modules into any Digital pins
Take paper and Sharpie
Draw black rectangle (approximately 1/2" x 2")
Fill in the rectangle

Upload

Upload the following code. The example below uses the D3 digital pin.

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// digital pin of Line Finder being calibrated
int signalPin =  3;

void setup()   
{
  // initialize the digital pin as an output
  pinMode(signalPin, INPUT);

  // initialize serial to display what line finder reads
  Serial.begin(9600);
}
void loop()
{
  // if a color is detected print 1, else print 0
  if (HIGH == digitalRead(signalPin))
    Serial.println(1);
  else  Serial.println(0);
}

Observe

Open Tools -> Serial Plotter to see the inputs. This will display the value the line finder detects. You'll also notice the red LED on the module lights up when you put your hand in front of the sensor. The goal is to adjust when this LED turns on so that the sensor detects when it is passed from black to white.

Calibrate the Modules 

Hold the module about eighth an inch from the black rectangle you drew so that both IR LEDs are over the black. Take a small screw driver turn the adjustable resistor clockwise slowly until you see that that red LED turns off. While holding the module half an inch away from the paper move it until both IR LEDs are over white and then turn the adjustable resistor slowly in either direction but just until the LED turns back on.

When the line finder is calibrated correctly the LED will be off when over the black and on over the white. If if didn't work that first time don't be discouraged! This part can be quite tricky. Keep moving the module over the black, turning the resistor until the LED turns off, moving it over the white, slowly turning the resistor just until the LED turns on, and checking the Serial Monitor / the red LED to see if the module is correctly calibrated.

Repeat this process for both line finder modules making sure to change the code provided to match the digital pin of the module you're calibrating. It is important that the line finders are calibrated half an inch away because they will be reading the encoder wheels which will be approximately half an inch away from the line finders.

Observe indicator LED on line finder turn on
Observe indicator LED on line finder turn on
Hold line finder module 1/2" above black rectangle
Use screwdriver to turn potentiometer clockwise until LED turns off
Turn potentiometer counterclockwise until red LED comes back on
LED should turn on when held 1/2" away from white part of paper
LED should turn off when held 1/2" away from black part of paper

Arrow Means Up 

There is an arrow engraved into the chassis. This shows the top or front of the chassis and kit. Any directions saying left, right, or bottom, will assuming this arrow is pointing ahead.

The ArrowThe Arrow

Peeling the Acrylic 

All the acrylic parts in Robotics Kit 1 have a protective film. Before assembling the kit, remove it.

A piece with the film
A piece with the film
Peel off the film
Peel off the film
One side done...
...and the other

Mounting the Line Finders 

Now that the line finders are calibrated you can mount them.

  1. Begin by grabbing the line finder modules, four M2 10mm screws, four M2 hex nuts, and two line finder mounts.

  2. Place the black part of the line finder module through the center cutout of the mount. The holes in the module should line up with the holes in the mount.

  3. Insert a M2 screw into both holes then flip over the piece. Attach a M2 hex nut to both screws and hand tighten.

  4. Repeat this for the second module. Note that you want the pieces to mirror each other and not be copies.

All the parts you need
All the parts you need
The socket
Should be over here when mounted
Take the line finder module
Place through slot
Take screw
Place in hole
Place in hole
Place in hole
Place in hole
Flip over
Take hex nut
Place on screw
Repeat for other screw and nut
Repeat for other screw and nut
Tighten down
This one is done
Repeat for other side
Repeat for other side
Socket should be up here

Securing Line Finders to Chassis 

Now grab two M3 10mm screws, two M3 hex nuts, and the chassis.

Insert into SLOT CInsert into SLOT C

  1. Now insert the mounts into slot C. One on each side. You want the black part of the line finder module facing out with the socket facing in.

  2. With the mounts pushed into the chassis, place a nut into the T shaped hole on the line finder mount. The nut should be parallel to the chassis.

  3. Using your fingers to holder the nut in place, screw a M3 10mm screw into the hole from the other side of the chassis. The screw should go through the hex nut. Make sure not to tighten the screw too much or you can damage the acrylic.

  4. Repeat this for the other mount. When you're done both mounts and modules should be securely attached so they don't wiggle.

All the parts
All the parts
Here is the C-Slot
Take a module
Line up with the slots
Place in slot
Socket pointing inward
A hex nut
It will go in this tiny slot
Take a hex slot
Slide into slot
Zoomed in
Flip over and take a screw
Insert from the top through the chassis
Screw into nut
Zoomed in
Repeat with other module
Both sockets are inward

Mounting the Motors and Encoder Wheel 

In order to mount the motors you'll need to mount the encoder wheel at the same time. For this you'll need the chassis, four motor mount pieces, the two encoder wheels, two of the stickers, four M3 30mm screws, four M3 nylon locking nuts, the two tires, and the two DC motors.

  1. Grab the stickers and encoder wheels. Peel off one of the stickers and carefully stick it to the encoding wheel. Try and line it up as neatly as possible with the edge of the wheel so that there is no excess hanging over the edge of the wheel. If any is over the edge, use scissors to trim it. Do this for both wheels using one sticker per wheel.
Stickers and wheels
Stickers and wheels
These are the encoder stickers
They go on the wheels
Peel a sticker
Peel a sticker
The center cutout is removed
Placed over a wheel
Placed over both wheels
  1. Insert two motor mount pieces into SLOT A so that it pushes through the chassis and the longer part is one the same side as the line finder mount. The largest hole should be pointed towards the double slits in the chassis or towards the back. This hole is where the motor axle is going, so orienting it this way ensures the axle is centered with the tire slot.

  2. Slide the motors into the mounts so that the axle goes into the largest hole and the screw holes line up with the screw holes on the mount. The axle should be centered with the tire slot.

  3. SLOT B is for the encoding wheel. Place the encoder wheel in the slot by lining up the hole on the encoder wheel with the axle of the motor. Adjust the position of the encoder wheel so that it may turn freely when the motor runs - meaning it should not be up against the motor mount or the edge of SLOT B. The sticker side of the wheel should face the line finder module.

  4. Take the other two motor mounts and place them on the outside of the motor. Place one screw through the hole above the chassis and another screw through the hole diagonal across. If you have the tools, tighten down a nylon locking nut. If not, a normal M3 hex nut will do just fine.

Do not over tighten. There should be no bends in the acrylic parts.

  1. You can put on the tires now.
Flipped over chassis and two mounts
Flipped over chassis and two mounts
This mount
Will go in this slot
These holes
Should be pointed up
Take the mount
Insert from the bottom
Inserted
Both inserted
This is the motor orientation
The motor holes line up with the mount holes
Adding the other motor
Grab the encoder wheels
They should be like this
Place on axis
The sticker should face the encoder
Grabbing the other mounts
Match up to motor
Match up to motor
Repeat on other side
Hardware parts needed
Take the screw
Insert into bottom hole
Insert into bottom hole
Grab locking nut
Tighten to the screw
Tighten to the screw
Tighten to the screw
You might need pliars
So using a hex nut instead is fine
Repeat for other side
Now flip over the chassis
Now flip over the chassis
Here are the other holes
Here are the other holes
Hardware needed
Take a screw
Insert into mount
Insert into mount
Take locking nut
Screw onto screw
Screw onto screw
Screw onto screw
Watch out for the tightness
This is perfect
This is too tight
Repeat for the otherside
Get the tires
Line them up
Tires on

Installing the Front wheel 

In order to balance your robot you'll need to install the front wheel. To do this grab the omni wheel, two M3 10mm standoffs, two M3 nylon locking nuts, and two M3 10mm screws.

  1. First screw the two M3 10mm screws into the two front holes of the chassis.

  2. Screw the standoffs onto these screws.

  3. Place the standoffs into the holes of the omni wheel, place hex nuts on the screws, and tighten. You want the wheel to be securely attached so consider using a wrench or pliers to really tighten the nylon locking nuts.

Parts needed
Parts needed
Take a screw
Place through chassis hole
Place through chassis hole
Take standoff
Tighten from under the chassis
Tightened standoff
Repeat for only side
Flipped over
Take wheel
Place over standoffs
Take a locking nut
And the other
Tighten
You need pliers for this. Substitute a hex nut if you don't have
Omni wheel setup
done

Removing the Jumper 

  1. First you need to remove a jumper on the motor driver to use the external battery holder. A jumper is just a piece of metal that connects two wires. The jumper on the driver is located in between the white cable port and the green screw terminal labeled VS and GND.

  2. Using your fingers or a screw driver pull it off. Place this with your Creator Set so it doesn't get lost.

Locate jumper on motor driver
Locate jumper on motor driver
Use a flathead screwdriver to remove the jumper by pulling it up and off the board
Remove the jumper
Jumper is removed

Mounting the Battery Holder 

Grab 2 M2 10 mm screws, two M2 hex nuts, and the battery holder.

  1. Place the battery holder on the front of the chassis so that the holes in the chassis are visible through the battery holder.

  2. Place both M2 screws through the battery holder then through the chassis.

  3. Hand tighten a M2 hex nut on each screw.

Parts needed
Parts needed
These holes
Will line up with these
Take the battery holder
Line up with chassis holes
Line up with chassis holes
Take a screw
Place into hole
Take a screw
Place into hole
Flip over
Take a nut
Tighten
Take the other nut
Tighten
Screws tightened down
Done

Mounting the I2C Motor Driver 

Grab 2 M2 10 mm screws and two M2 hex nuts. On the I2C Motor Driver there are a total of 3 green screw terminal blocks. The one by the socket is for the battery while the other two are for the motor.

  1. Unscrew the screw inside the battery screw terminal. The screws will NOT comes out. Just a few turns are fine.

  2. Place the RED wire coming from the battery holder into the slot marked VS on the screw terminal. Tighten that screw.

  3. Place the BLACK wire coming from the battery holder into the slot marked GND on the screw terminal. Tighten that screw.

  4. Place the I2C Motor Driver, with the socket facing forward, in the middle of the chassis.

  5. Place one screw in the mounting hole in the middle right of the board and one in the top left.

  6. Flip the board and chassis over then hand tighten a nut to both screws.

I2C Motor Driver
I2C Motor Driver
Battery terminals
Loosen
Loosen
Red wire from battery holder
Into VS terminal
Tighten
All tightened down
Black wire from battery holder
Into GND terminal
Tighten
Ready to mount
On the chassis
This socket
Is towards the front
These are the mounting holes
Add screws into these
Hold down
Flip over
Add a nut
Add a nut
Tighten both
Flip back over
Done

Connecting the Motors 

Each motor should have a red and black jumper wire coming off of it.

  1. Loosen the two motor screw terminal blocks. The screws will NOT comes out. Just a few turns are fine.

  2. Place the RED wires into M1+ and M2+. Which ever is closest. Then tighten those screws.

  3. Place the BLACK wires into M1- and M2-. Each wire pair should go to its own screw terminal block. Then tighten those screws.

Motor terminals
Motor terminals
Loosen all terminals
Loosen all terminals
Take red motor wires
Insert into + terminals
Tighten both
Tighten both
Take black motor wires
Insert into - terminals
Tighten both
Tighten both
Done

Mounting the Arduino 

For this part we need the Arduino and the black expansion shield separated. We will also need two M3 10mm screws and two M3 hex nuts.

  1. Place the Arduino with its USB port and power jack facing towards the left on the chassis. The bottom right Arduino mounting hole should match up to the outer slot in the chassis. The top left Arduino mounting hole should line up inside the center bottom slot.

  2. Place a screw in each of the holes described previously. The top left one will be slightly crooked.

  3. Flip over the chassis and hand tighten a hex nut to both screws.

  4. Flip the chassis over again. The black expansion board can be put back on top of the Arduino.

Arduino and shield
Arduino and shield
These must be separated
Separated
Bottom of chassis
Mounting points
Arduino orientation
Insert screw
Insert other screw
Hold down screws
Flip over
Add a nut
Add a nut
Add a nut
Tighten both
Flip back over
Take shield
Line up with Arduino headers
Press down
Done

Attaching the Cables 

We will need 3 standard cables to get the robot up and running.

  1. Take a cable and plug one end into the motor driver socket and the other into any I2C port.

  2. Use two cables and gently plug them into the line finder modules if they aren't already attached. The long slots on the chassis have little notches in them. These allow you to thread the cables through the board to the other side.

  3. Take each of the line finder cables and push them through to the top of the robot. To do this take a close look at the clips at the ends of the cables. On one side of the clips there's a notch that fits into the notch in the slots on the chassis. Align these to push the cables through.

  4. Plug the left line finder into Digital socket D3 and the right line finder in to Digital socket D2.

Chassis and cables
Chassis and cables
Take a cable
Unwrap
Place one end in the Motor Driver socket
The other into any I2C Socket
Flip over
Flip over
Table both cables
Unwrap them
One side into a line finder socket
Then feed through the chassis slot to the top side
Like that
One side into a line finder socket
Then feed through the chassis slot to the top side
Like that
Flip back over
Flip back over
Right side line finder
To D2
Plugged in
Right side to D3
Right side to D3

Next section 

Now all the hardware is mounted. It is time to test the motors and learn how to control the WiFi Robot.