How to Build a Simple DIY Arduino Robot that Actually Moves
Building your own Arduino robot from scratch can be a fun and rewarding experience. With just a few common electronic components, some basic coding skills, and a bit of patience, you can have your own custom robot up and moving around. Here is a step-by-step guide on how to build a simple DIY Arduino robot that can actually move under its own control.
Selecting the Right Arduino Board and Motors
The first step is selecting the right Arduino microcontroller board and motors for your robot.
Arduino Board
For a beginner robotics project like this, I recommend using an Arduino Uno board. The Arduino Uno is inexpensive, widely available, and has all the necessary pins and processing power to control a simple robot.
Some key specs of the Arduino Uno:
- Microcontroller: ATmega328P
- Operating Voltage: 5V
- Digital I/O Pins: 14 (6 of which can be PWM)
- Analog Input Pins: 6
- Flash Memory: 32 KB
- SRAM: 2 KB
- Clock Speed: 16 MHz
The 14 digital pins will allow us to connect sensors and control motors, while the USB connection lets us transfer code onto the board.
Motors
For the motors, two common options are small DC motors or servo motors.
DC motors are simple and provide continuous rotation, allowing the robot to drive around. Servo motors only rotate part of a turn, but offer more precise control.
For a basic moving robot, I recommend using two small DC motors with built-in gear boxes and wheels. Look for motors that operate at 3-6V, which matches the 5V output of the Arduino. The gear box helps reduce speed while increasing torque.
Assembling the Chassis
Now it's time to assemble a simple chassis to mount the Arduino and motors onto. Here are a few options:
- A rectangle or square shape made from cardboard, wood, acrylic etc.
- Lego pieces snapped together
- A ready-made robot chassis kit
I prefer using sturdy cardboard or acrylic sheets as they are easy to cut, drill, and glue to create a custom chassis. Make sure to leave room for the Arduino, breadboard, motors and batteries.
Below is a simple cardboard chassis I created:
The chassis provides a sturdy base for all the components.
Adding the Circuitry
Next, we need to assemble the electronic components that will power and control the robot. This circuitry includes:
- Arduino Uno - The brains of the robot
- Breadboard - For connecting components
- DC motors - For locomotion
- Motor driver - To amplify power for the motors
- Batteries - A power source, such as AA batteries
Schematics for wiring up these components can be found online. Essentially, the motor driver takes a control signal from the Arduino and provides the necessary amperage for the motors.
The exact wiring isn't critical. As long as the motors, motor driver and Arduino are connected properly, the robot will be able to move.
Coding the Arduino
Now for the software that will bring the robot to life. The Arduino code has just a few key elements:
- Initializing pins - Set control pins for the motors as outputs
- Main control loop - Repeats continuously
- Motor functions - Routines to spin the motors forward, backward, or stop
- Delay functions - Pause the program for set time periods
By calling the motor functions within the loop and adding delays, we can make the robot move forward, turn, reverse, and more.
Here is a very simple example:
```cpp
// Set motor control pins as outputs
void setup() {
pinMode(leftMotorPin, OUTPUT);
pinMode(rightMotorPin, OUTPUT);
}
void loop() {
// Forward
forward(2000);
// Pause
delay(500);
// Right turn
rightTurn(1000);
// Pause
delay(500);
// Backwards
reverse(2000);
// Pause
delay(500);
// Left turn
leftTurn(1000);
// Pause
delay(500);
}
// Motor functions
void forward(int time) {
// Spin motors forward
digitalWrite(leftMotorPin, HIGH);
digitalWrite(rightMotorPin, HIGH);
// Pause
delay(time);
// Stop motors
digitalWrite(leftMotorPin, LOW);
digitalWrite(rightMotorPin, LOW);
}
void rightTurn(int time) {
// Right motor forward, left motor stopped
digitalWrite(leftMotorPin, LOW);
digitalWrite(rightMotorPin, HIGH);
// Pause
delay(time);
// Stop both motors
digitalWrite(leftMotorPin, LOW);
digitalWrite(rightMotorPin, LOW);
}
// Repeat for leftTurn() and reverse() functions
```
This simple program will make the robot drive forward, turn right, reverse, turn left, and repeat! The full code can be customized with more functionality.
Testing and Troubleshooting
Once the hardware is assembled and software uploaded, it's time for testing! Place the robot on the ground and make sure the wheels can spin freely. Then connect the battery and watch it go.
Some common issues include:
- Motors wiring reversed - Swap polarity
- Bug in code - Check for errors
- Loose connections - Check breadboard
- Battery low - Use new batteries
With some tweaking and adjustments, your Arduino robot will soon be driving around!
Customizing Your Robot
A basic mobile robot is complete, but now the fun begins! Here are some ideas for customizing and expanding your Arduino robot:
- Add sensors like ultrasonic, infrared or light sensors for obstacle avoidance and line following capabilities
- Mount a Raspberry Pi to give your robot vision, speech and more AI abilities
- Control remotely with Bluetooth or WiFi connectivity
- Make a robotic arm for picking up objects
- Let your creativity run wild with the chassis design - add themes, colors, and decoration
The possibilities are endless when you build it yourself. Start simple, but always be looking for ways to improve your Arduino robot creation.
So there you have it - a complete guide to building a DIY Arduino robot that can actually move around on its own. With the help of this step-by-step tutorial, you can now bring your own autonomous robot to life!