Position Coordination Aid for Blind Persons Based on LoRa Point to Point

Abstract

Conventional or electronic sticks are one of the tools that are often used by people with blind persons for independent activities. Both tools have limitations that cannot provide a sense of comfort in the form of information on the distance position between blind persons. In this research, electronic hardware is designed and built, which is integrated with conventional sticks. Designs and aids are made to exchange positional information on the distance between blind persons for normal and emergency conditions. The two electronic hardware consists of a global position system (GPS) modules, LoRa radio, DF mini-player, liquid crystal display (LCD), button, and a microcontroller. Communication between electronic hardware uses a point to point topology with half-duplex communication. Each hardware device is planted with source ID and destination ID, so that as soon as the push-button is pressed, the microcontroller reads the coordinate point data from the GPS module. The combined coordinate data and source ID are transmitted to the destination ID via LoRa radio and will exchange coordinate data instead. Furthermore, the two coordinate data in each microcontroller hardware is converted into distance information (meters) using the Haversine algorithm. Distance information is displayed on the LCD and converted into sound output through the DF mini-player speaker. The result of system functionality testing, the average percentage error is 1.21%, and the reading of all the resulting distance data can sound. Testing the GPS module obtained the percentage of conformity of the coordinates with an accuracy of 99%. Testing the data communication system obtained the maximum distance on the LoRa module as far as 500 meters. The received signal strength value (RSSI) parameter has no effect on the distance tested, and the receiver's packet loss parameter will be very influential if it is blocked by an object (obstacle).

Alat Bantu Koordinasi Jarak Dan Posisi Disabilitas Netra Berbasis Radio Frekuensi Menggunakan Haversine-Bearing

“…Penelitian terkait alat bantu tongkat elektronik untuk PDSN dalam aktivitas kesehariannya telah banyak dilakukan. Mulai dari fitur tongkat yang dapat memberikan informasi titik koordinat lokasi PDSN [2]- [4], [8], [9] dan fitur mendeteksi objek [2]- [7]. Kombinasi penggunaan modul GPS dan sensor deteksi objek dalam satu sistem.…”

“…Penelitian terkait informasi titik koordinat lokasi PDSN untuk pengukuran jarak menggunakan algoritma Haversine dan komunikasi radio frekuensi LoRa point to point [8]- [10]. Sistem dibuat Otomatis titik koordinat latitude longitude dari modul GPS ditransmisikan melalui LoRa ke alat bantu (B), maupun sebaliknya (titik koordinat B ditransmisikan ke A).…”

“…Menggunakan algoritma Haversine setiap alat bantu secara mandiri menghitung jarak antar titik koordinat dan hasilnya dikeluarkan dalam informasi suara. Rata-rata persentasi kesalahan pengukuran jarak 1,21%, GPS 99% pada jarak maksimum 500 m [8]. Sedangkan alat bantu dengan keluaran informasi braille text (jam tangan) ketepatan konversi 100 % dengan rata-rata akurasi kesalahan jarak 0,61 m terhadap pengukuran manual menggunakan meteran [9].…”