Introduction: Troubleshooting Obstacle Avoiding Robot Errors
Table of Contents
Obstacle-avoiding robots are a fantastic way to explore robotics and Arduino programming. However, errors like AFMotor.h: No such file or directory and NewPing.h can be frustrating for both beginners and experienced users. These errors often occur due to missing or outdated libraries, and this blog will walk you through the process of fixing them. Let’s solve these challenges together step-by-step and get your robot back on track!

What Causes the AFMotor.h and NewPing.h Errors?
Before diving into the solution, it’s essential to understand why these errors occur.
- Missing Libraries:
The Arduino IDE may not recognize the required libraries like AFMotor.h and NewPing.h because they haven’t been installed. - Outdated Libraries:
You may have an older version of the library that lacks compatibility with your current Arduino IDE. - Incorrect Code References:
Sometimes, typos or misplaced files in your project directory can also trigger these errors.
Don’t worry! Fixing these issues is straightforward if you follow the steps below.
How to Fix the AFMotor.h and NewPing.h Errors
Here’s a step-by-step guide to resolving the errors.
1. Update or Install the Required Libraries
To fix the AFMotor.h and NewPing.h errors, you need the latest versions of the required libraries. Follow these instructions:
- AFMotor.h Library (Adafruit Motor Shield):
- Visit the Adafruit Motor Shield Library GitHub page.
- Click on the green Code button and select Download ZIP.
- Open the Arduino IDE, go to Sketch > Include Library > Add .ZIP Library, and select the downloaded ZIP file.
- NewPing.h Library (Ultrasonic Sensor):
- Navigate to the NewPing Library GitHub page.
- Download the ZIP file and install it in the Arduino IDE using the same method as above.
- Servo Library (if Required):
- The Servo library is often included with the Arduino IDE. If not, download it from the Arduino Libraries GitHub page.
- Install it similarly to the other libraries.
2. Verify the Installation
After installing the libraries:
- Go to Sketch > Include Library in the Arduino IDE.
- Ensure that AFMotor and NewPing are listed.
- If not, double-check the installation process or the downloaded files.
3. Check the Code and Adjust References
Ensure your code references the libraries correctly. Here’s an example snippet to help you avoid common mistakes:
Obstacle Avoiding Robot Code
#include <AFMotor.h> // For motor control
#include <NewPing.h> // For ultrasonic sensor
#include <Servo.h> // For servo control
// Pin definitions
#define TRIG_PIN 12 // Trigger pin for ultrasonic sensor
#define ECHO_PIN 11 // Echo pin for ultrasonic sensor
#define MAX_DISTANCE 200 // Maximum distance to measure (in cm)
// Motor connections
AF_DCMotor leftMotor(1); // Left motor connected to port 1
AF_DCMotor rightMotor(2); // Right motor connected to port 2
// Servo
Servo scanServo; // Servo for scanning
#define SERVO_PIN 9 // Servo pin
// Constants
#define SAFE_DISTANCE 20 // Minimum safe distance from an obstacle (in cm)
#define SCAN_STEP 15 // Angle step for servo scanning
#define MAX_SERVO_ANGLE 180 // Maximum servo angle
#define MIN_SERVO_ANGLE 0 // Minimum servo angle
// Ultrasonic sensor
NewPing sonar(TRIG_PIN, ECHO_PIN, MAX_DISTANCE);
// Variables
int currentServoAngle = 90; // Start servo at center position
void setup() {
Serial.begin(9600); // Initialize serial communication for debugging
scanServo.attach(SERVO_PIN); // Attach servo to the pin
scanServo.write(currentServoAngle); // Move servo to center position
// Initialize motors
leftMotor.setSpeed(150); // Set initial motor speed
rightMotor.setSpeed(150);
}
void loop() {
int distance = measureDistance(); // Measure distance ahead
if (distance < SAFE_DISTANCE) { // Obstacle detected
stopMotors(); // Stop the motors
avoidObstacle(); // Execute avoidance maneuver
} else {
moveForward(); // No obstacle, move forward
}
}
// Function to measure distance using the ultrasonic sensor
int measureDistance() {
delay(50); // Short delay for stable readings
return sonar.ping_cm();
}
// Function to move the robot forward
void moveForward() {
leftMotor.setSpeed(150);
rightMotor.setSpeed(150);
leftMotor.run(FORWARD);
rightMotor.run(FORWARD);
}
// Function to stop the motors
void stopMotors() {
leftMotor.run(RELEASE);
rightMotor.run(RELEASE);
}
// Function to move the robot backward
void moveBackward() {
leftMotor.setSpeed(150);
rightMotor.setSpeed(150);
leftMotor.run(BACKWARD);
rightMotor.run(BACKWARD);
delay(500); // Move backward for half a second
stopMotors();
}
// Function to turn the robot left
void turnLeft() {
leftMotor.setSpeed(100); // Slow down left motor
rightMotor.setSpeed(150); // Maintain speed on right motor
leftMotor.run(BACKWARD);
rightMotor.run(FORWARD);
delay(500); // Turn for half a second
stopMotors();
}
// Function to turn the robot right
void turnRight() {
leftMotor.setSpeed(150); // Maintain speed on left motor
rightMotor.setSpeed(100); // Slow down right motor
leftMotor.run(FORWARD);
rightMotor.run(BACKWARD);
delay(500); // Turn for half a second
stopMotors();
}
// Function to avoid obstacle
void avoidObstacle() {
moveBackward(); // Move backward first
// Scan left and right distances
int leftDistance = scanObstacle(MIN_SERVO_ANGLE); // Measure distance to the left
int rightDistance = scanObstacle(MAX_SERVO_ANGLE); // Measure distance to the right
// Decide which way to turn based on distance
if (leftDistance > rightDistance) {
turnLeft(); // More space on the left
} else {
turnRight(); // More space on the right
}
// Reset servo to center
scanServo.write(90);
}
// Function to scan for obstacles with the servo
int scanObstacle(int angle) {
scanServo.write(angle); // Move servo to specified angle
delay(500); // Wait for servo to move
int distance = measureDistance(); // Measure distance
return distance;
}
- Make sure you are including the libraries with the correct case sensitivity. For instance, write
#include <AFMotor.h>
instead of#include <afmotor.h>
.
4. Replace Deprecated Functions in the Code
Older versions of the libraries may have deprecated certain functions. For example:
- Replace
AFMotor
functions with their updated counterparts. - Update the syntax for
NewPing
calls based on the latest documentation from the NewPing GitHub page.
5. Reconfigure the Library Paths
If you’re still facing errors, the problem might be with library paths.
- Go to File > Preferences in the Arduino IDE.
- Check the Sketchbook location for the correct path.
- Ensure all your libraries are in the
libraries
folder within this path.
Tips for Smooth Arduino Programming
- Keep Libraries Updated: Regularly update libraries through the Arduino IDE or GitHub.
- Backup Your Code: Before making significant changes, save a copy of your current project.
- Test with Examples: Use example sketches from the library to confirm it’s working correctly.
- Organize Your Sketches: Maintain a clear folder structure to avoid misplaced files.
Frequently Asked Questions (FAQs)
1. Why am I getting “No such file or directory” errors?
This happens when the Arduino IDE cannot find the required library files. Ensure the library is installed and correctly referenced in your code.
2. Can I use older versions of the libraries?
While possible, using older versions may result in compatibility issues. It’s best to download the latest releases from GitHub.
3. What if the problem persists?
Double-check your library paths, code references, and ensure the correct board and port are selected in the Arduino IDE.
Conclusion: Fixing Arduino Errors Made Easy
Solving the AFMotor.h: No such file or directory and NewPing.h errors doesn’t have to be daunting. By installing the correct libraries, verifying their paths, and updating your code, you can quickly resolve these issues and continue building your obstacle-avoiding robot.
Now that you’ve resolved these errors, it’s time to test your robot. Watch it navigate obstacles seamlessly while you enjoy the satisfaction of a job well done!
Download BlueBot Controller App and start your journey today!