OttoDIY Robot

This is a step-by-step walkthrough of how I made my OttoDIY robot.

I tried to include as many pictures as possible to avoid any confusion.

Otto's Parts

• 1 x Otto Head
• 1 x Otto Body
• 2 x Otto Legs
• 2 x Otto Feet
• 1 x Ultrasonic Sensor
• 4 x Servo Motors
• 2 x Full Servo Horns
• 3 x Half Servo Horns
• 1 x Nano ATmega
• 1 x Nano Shield
• 1 x Buzzer
• 1 x Button
• 1 x 9V Battery Holder
• 1 x 9V Battery
• 6 x Female/Female Wires
• 1 x USB-A/Mini-USB Cable
• 10 x 8mm Screws
• 4 x 4mm Screws

Tools

• Magnetic Screw Driver
• XACTO Knife
• Wire Stripper
• Electrical Tape
• Grip Tape
• Computer

Need:

• Computer

Before building, I like to go ahead and set up any necessary software.

1. Head over to https://www.arduino.cc/en/software and choose the download option that works for your computer
2. Follow the prompted directions to complete the download
3. Go to https://github.com/OttoDIY/OttoDIYLib/ and again, follow the on-screen directions to download the Otto libraries

Need:

• 2 x Servo Motors
• 1 x Otto Body
• 4 x 8mm Screws

We'll start by attaching the two motors that go into Otto's body.

1. Line up the servos on either side of Otto's body so that they align with the internal grooves
2. Fasten the servos with two screws each

Need:

• 2 x Full Servo Horns
• 2 x Otto Legs
• 2 x 4mm Screws

Next, we'll attach Otto's legs.

1. Take a full servo horn and trim its longer sides. One side should be cut just above 2 notches from the center and the other just above 5 notches
2. Repeat with another full servo horn. You should have two identical pieces that look like image 2
3. Place a trimmed horn into each leg
4. Attach a leg to the white part of each servo protruding from the bottom of Otto's body. The longer sides of the servo horns in the legs should be facing Otto's front
5. Make sure the servos are at the center of their rotation. Then, screw in the legs through the center of the horns

Need:

• 2 x Otto Feet
• 2 x Servo Motors
• 2 x Half Servo Horns
• 2 x 4mm Screws
• 2 x 8mm Screws

Now, we'll be putting together Otto's feet.

1. Place a half servo horn into each foot. Each foot is labeled either left or right; keep this in mind
2. Use 8mm screws to fasten the horns to the feet through the hole that's closer to each foot's bottom
3. Attach a servo motor to each horn so that the wires face the bottom of Otto's foot. Again, make sure the servos are at the center of their rotation
4. Use 4mm screws to fasten the servo motors to the horns

Need:

• 2 x 8mm Screws
• Everything built so far

The following step is just putting together what we have so far; we'll be attaching Otto's feet to its legs. This is where a magnetic screwdriver comes up big.

1. Feed the wires of each foot through the gap in their respective leg (shown in image 2). Make sure the right foot is on the right leg, and the left on the left. Otto should look like image 3
2. Use 8mm screws to fasten the feet to the legs through the hole in the servo. You'll have to tighten the screw via the hole on the opposite side of the leg

Need:

• 1 x Nano ATmega
• 1 x Nano Shield

In this step, we'll be giving Otto its brain.

1. Attach the ATmega to the shield. Make sure the ports of each are facing the same direction
2. Wire the servos to the top part of the shield. Remember, brown goes to Ground (G) and orange goes to signal (S). Below is a guide for the wiring

SERVO --> COLUMN

• Right Foot --> 5
• Left Foot --> 4
• Right Leg --> 3
• Left Leg --> 2

Need:

• 1 x USB-A/Mini-USB Cable
• Computer

Before continuing the build, it's important to make sure all your motors work as intended.

1. Open Arduino IDE
2. Use the cable to connect Otto to your computer
3. In the IDE, go to File -> Examples -> Otto DIYLib -> Otto_allmoves
4. Select your board, then verify and upload the code. Otto should begin cycling through all of its movements.

Need:

• 1 x Buzzer
• 1 x Ultrasonic Sensor
• 6 x Female/Female Wires

Next, Otto gets eyes and a voice.

1. Attach 4 wires to the pins on the sensor. Keep in mind which pin has what color to make the wiring easier
2. Attach 2 wires to the buzzer. Again, remember your colors
3. Place the sensor in Otto's eye slots with the wires facing out
4. Wire the sensor and buzzer to the top part of the microcontroller. Below is a guide for wiring. The last image is a reference for how your wiring should look. Ignore the placement of the microcontroller and the bottom 2 wires for now

SENSOR PIN -> MICROCONTROLLER (COLUMN, ROW)

• VCC -> (9, V)
• Trig -> (8, S)
• Echo -> (9, S)
• GND -> (8, G)

BUZZER -> MICROCONTROLLER (COLUMN, ROW)

• Positive -> (13, S)
• Negative -> (13, G)

Need:

• 1 x Button
• 1 x 9V Battery
• 1 x 9V Battery Holder

Afterward, we can prepare the battery and the button.

1. Put the battery into the battery holder
2. Wire the black lead of the battery to GND across the bottom of the board
3. Attach the red lead of the battery to either side of the button
4. Wire the other side of the button to VIN on the same part of the board
5. Place the battery into the center gap of Otto's body
6. (OPTIONAL) The placement of the button is up to you. I wanted mine fully outside of Otto, so I filed down a hole to fit the button through Otto's backside

Need:

• Everything built so far
• 2 x 8mm Screws

Now that all wires are in place, we can secure the microcontroller.

1. Place the microcontroller into Otto's head so that the ports line up with their respective holes
2. Use 2 screws to secure the microcontroller. You can use more screws if you have them, but only 2 are necessary

Need:

• 1 x Otto Head, prepared
• 1 x Otto Body, prepared

Otto is ready to be made whole!

1. Carefully fit all of Otto's components as best as you can into its body/head
2. Insert Otto's head on its body. Make sure the eyes are facing forward

Need:

• Grip Tape

I wanted to keep Otto from sliding around too much, so I made Otto some "shoes"

1. Cut out a few strips of grip tape that fit on the bottom of Otto's feet. The size and shape don't particularly matter
2. Peel off the adhesive cover of the grip tape and stick to the bottom of Otto's feet

With that, Otto is done and ready to be programmed. I'll include a link below with some helpful information regarding Otto's functions.

https://docs.google.com/presentation/d/1rhB4QGtb_8VBEtdeulk5ty5Jp9uqi-nR-Xp2ktzbUxQ/edit#slide=id.g1028c818c3c_0_0