A Microcontroller-Based Car Parking Warning System for Improved Parking Safety Using Ultrasonic Sensor
by Engr. Bernard C. Fabro, John Aarom P. Mina, Jose Alfonso P. Labrador, Kinnah Charish I. Torre, Mark Anthony A. Zamora, Mark Yancee P. Vicente, Ryan N. Gripon
Published: January 23, 2026 • DOI: 10.51244/IJRSI.2026.13010016
Abstract
The increasing number of vehicles on the road has led to a higher risk of accidents, especially during reverse parking and in congested traffic conditions. Many minor collisions occur due to limited rear visibility and the driver’s inability to accurately judge distance. As a response to this problem, this project research focuses on the development of a low-cost and reliable reverse parking assistance system using an Ultrasonic Sensor and an Arduino Uno R3. The background of this study is rooted in the need for an affordable alternative to commercial parking sensors that can still provide accurate and real-time obstacle detection.
The main objective of this research is to detect obstacles located at the rear of a vehicle and provide timely warnings to help avoid collisions while parking or moving slowly in traffic. Specifically, the system aims to measure the distance between the vehicle and nearby obstacles and alert the driver through visual and audio indicators based on the detected distance.
The methodology of the study involves integrating an ultrasonic sensor with an Arduino Uno R3 microcontroller. The ultrasonic sensor continuously measures the distance of objects behind the vehicle by emitting and receiving sound waves. Based on the measured distance, the Arduino processes the data and activates a buzzer and LEDs. The LEDs light up sequentially in green, yellow, and red to indicate safe, caution, and danger zones, respectively, while the buzzer provides an audible warning as obstacles get closer.
The key results of the project show that the system is capable of accurately detecting obstacles in real-time and effectively providing distance-based alerts. In conclusion, the proposed system demonstrates a practical and efficient solution for reverse parking assistance, with potential for further improvement and application in advanced vehicle safety systems.