How to Use HC-SR05: Examples, Pinouts, and Specs

The HC-SR05 is an ultrasonic sensor designed for distance measurement. It operates by emitting an ultrasonic wave and measuring the time it takes for the echo to return. This time delay is then used to calculate the distance to an object. The HC-SR05 is widely used in various applications, including robotics, obstacle detection, and distance measurement systems.

1. Power the Sensor: Connect the VCC pin to a 5V power supply and the GND pin to ground.
2. Trigger the Sensor: Send a 10µs pulse to the Trig pin to initiate a measurement.
3. Read the Echo: Measure the width of the pulse on the Echo pin, which is proportional to the distance to the object.

• Stable Power Supply: Ensure a stable 5V power supply to avoid inaccurate measurements.
• Avoid Obstacles: Ensure there are no obstacles within the sensor's measuring angle that could interfere with the ultrasonic waves.
• Mounting: Mount the sensor securely to avoid vibrations that could affect the measurements.

// HC-SR05 Ultrasonic Sensor - Arduino UNO Example Code

const int trigPin = 9; // Trigger pin connected to digital pin 9
const int echoPin = 10; // Echo pin connected to digital pin 10

void setup() {
  Serial.begin(9600); // Initialize serial communication at 9600 baud rate
  pinMode(trigPin, OUTPUT); // Set trigPin as an output
  pinMode(echoPin, INPUT); // Set echoPin as an input
}

void loop() {
  long duration, distance;
  
  // Clear the trigPin by setting it LOW
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  
  // Set the trigPin HIGH for 10 microseconds to send out the pulse
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  // Read the echoPin, which returns the duration of the pulse
  duration = pulseIn(echoPin, HIGH);
  
  // Calculate the distance (duration / 2) * speed of sound (34300 cm/s)
  distance = (duration / 2) * 0.0343;
  
  // Print the distance to the Serial Monitor
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
  
  delay(500); // Wait for 500 milliseconds before the next measurement
}

1. No Output or Incorrect Readings:

   • Check Connections: Ensure all connections are secure and correct.
   • Power Supply: Verify that the sensor is receiving a stable 5V power supply.
   • Trigger Pulse: Ensure the trigger pulse is 10µs.

2. Inconsistent Measurements:

   • Interference: Ensure there are no obstacles or reflective surfaces within the sensor's measuring angle.
   • Mounting: Ensure the sensor is mounted securely to avoid vibrations.

Q: What is the maximum range of the HC-SR05? A: The maximum range is 4 meters.

Q: What is the minimum range of the HC-SR05? A: The minimum range is 2 cm.

Q: Can the HC-SR05 be used outdoors? A: While it can be used outdoors, it is recommended to protect it from direct exposure to harsh weather conditions.

Q: How accurate is the HC-SR05? A: The HC-SR05 has an accuracy of approximately 3mm.

By following this documentation, users can effectively integrate the HC-SR05 ultrasonic sensor into their projects, ensuring accurate and reliable distance measurements.