Orientacart: Assistive Navigation Cart for the Visually Impaired Using RFID and Line Following

The increasing demand for inclusive retail environments has highlighted the navigation challenges faced by visually impaired individuals in large supermarkets and shopping complexes. Existing smart-cart systems primarily focus on automated billing, product identification, or retail analytics, while neglecting mobility accessibility. This paper presents OrientaCart, a low-cost assistive following, radio-frequency identification (RFID) junction routing, and ultrasonic obstacle detection under an ESP32 controller. User commands are received via a Bluetooth-based Android application, and auditory guidance is provided by a DFPlayer Mini MP3 module that plays pre-recorded prompts through a 3 W speaker. The prototype was validated on a 10 m indoor track with four junction tags at a constant speed of 0.30 m/s, achieving 95% RFID tag-read accuracy and a mean obstacle-stop latency of 0.5 s. Compared with prior smart carts and mobile robots, OrientaCart offers an accessibility-first design, predictable behavior without camera-based perception, and a commercial bill of materials (BOM) below ₹6,500. The proposed hybrid protocol demonstrates that reliable assistive navigation can be achieved using embedded sensing and event-driven control, supporting scalable deployment in supermarkets and malls.