The HC-SR04 is a popular ultrasonic sensor used to measure distances accurately using sound waves. It operates by sending out a high-frequency ultrasonic pulse and measuring the time it takes for the echo to bounce back from an object. This time is then converted into distance using simple calculations.
Key Features:
Operating Voltage: 5V DC
Measuring Range: 2 cm to 400 cm (0.02 m to 4 m)
Accuracy: ±3 mm
Operating Frequency: 40 kHz
Trigger Input Signal: 10µs TTL pulse
Echo Output Signal: TTL level signal proportional to distance
Interface: 4 Pins – VCC, Trig, Echo, GND
Dimensions: Approx. 45mm x 20mm x 15mm
How It Works:
Trigger: A 10µs pulse is sent to the Trig pin.
Ultrasonic Burst: The sensor emits 8 ultrasonic waves at 40 kHz.
Echo Detection: The Echo pin stays HIGH until the waves return after hitting an object.
Distance Calculation: The duration of the HIGH signal is used to calculate the distance:
Applications:
Obstacle avoidance robots
Distance measurement systems
Level detection (water tank, bins)
Automated parking systems
Security systems
HC SR04 Ultrasonic sensor
At Paras Projects, we believe in full honesty and transparency. That’s why we’ve introduced a Video Proof System for every robotics kit order.
🎥 1. Project Working Videos
Before dispatch, we test each robot kit and record a video showing that it is fully working and functional. This helps you understand how the kit performs and ensures you receive exactly what is promised.
📦 2. Packing Videos
We carefully pack each kit, and while doing so, we record the entire packaging process. This includes showing all components being added to the box to avoid confusion or claims about missing parts.
✅ Why This Matters:
Prevents fake refund requests
Builds customer trust
Helps students understand the assembly process
Ensures full quality control from our side
We share these videos privately with each customer if needed.