A Low-Cost Dual-Sensor Navigation Aid for the Visually Impaired: Development and Evaluation

The number of visually impaired individuals is increasing globally, posing challenges to safe and independent mobility. This paper presents the development and testing of a low-cost dual-sensor navigation aid that combines ultrasonic and passive infrared (PIR) sensors to detect obstacles and provide multimodal feedback through vibration, sound, and light signals. The prototype was constructed using an Arduino Nano, HC-SR04 ultrasonic sensor, PIR sensor, buzzer, vibration motor, and LED, enclosed in a protective casing. Pilot tests were conducted to evaluate detection accuracy at varying distances. Results showed that the system achieved reliable obstacle detection within 120 cm, with accuracy decreasing at longer ranges. The device demonstrates the potential of combining low-cost sensors to improve navigation safety for visually impaired users. Limitations of the current prototype and directions for future enhancements, including outdoor testing and integration with GPS, are also discussed.