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Parking Assistant System
Introduction
The proposed system is an intelligent parking assistant designed to monitor the rear of a vehicle using three reference points. The goal of the project is to prevent collisions by providing real-time visual, auditory, and numerical feedback.
Utility: Helps drivers estimate distance in blind spots.
Differentiator: Unlike basic systems, it uses three sensors to cover the entire width of the bumper (left, center, right).
General Description
The system reads distance data from three ultrasonic sensors and processes it using the ATmega328P microcontroller.
Features:
- Visual feedback: 3 RGB LEDs that change color (Green → Yellow → Red) depending on the proximity of obstacles for each zone.
- Auditory feedback: A passive buzzer that emits intermittent beeps, with frequency increasing as the car approaches an object.
- Display: The LCD shows the distance in centimeters for each of the three zones (L: XX cm | C: XX cm | R: XX cm).
Hardware Design
Component List:
| Component | Role in the project |
|---|---|
| ATmega328P-XMINI | System brain; processes signals and controls peripherals |
| 3× HC-SR04 | Distance measurement using ultrasonic waves (Left, Center, Right) |
| 3× RGB LEDs (CC) | Optical indicator for each sensor (Green = Safe, Red = Stop) |
| Passive Buzzer | Variable sound alarm |
| LCD 16×2 | Displays measured distances |
Electrical Diagram:
Software Design
The program logic is based on calculating the round-trip time of the sound signal:$$Distance = \frac{Time \times Speed of Sound}{2}$$ Algorithm structure:
- Initialization: Configure I/O pins, timers for PWM (buzzer/LED), and LCD interface.
- Main loop:
- Sequentially trigger Sensor 1, then 2, then 3 (to avoid interference).
- Calculate distance for each sensor.
- Update LED states (e.g., below 10 cm → Red).
- Compute buzzer “beep” frequency based on the smallest detected distance.
- Update LCD display.
Results
The system achieves an accuracy of approximately 1–2 cm. The interface is intuitive, allowing the driver to quickly identify which part of the car is closest to an obstacle.
Conclusions
The implementation on the ATmega328P demonstrates efficient handling of multiple sensors simultaneously using interrupts and timers. The project is scalable and can be integrated into any small vehicle.
