The idea is to use RFID/NFC tags placed in a grid pattern on ground. The robot contains a “map” of the RFID/NFC tags ID numbers. and Using this number knows where it is on the map. (under the strictest this robot uses NFC)
I am using a small home/student/educational robot called a Bitty Bot Rover - It’s a 2 wheeled robot, with a Arduino Mega 2560, and L298 motor driver. The battery is 9v. It’s a simple 2 wheeled robot, and any should work for this project.
The project is still a work in progress, but I will admit, it’s a slow work in progress. And a prove of concept for a 2 wheel robots.
Introduction: This type of indoor location has been used for years inside factories and warehouses. Mainly with 4 wheeled robots that are expensive, and have some type of omin-wheel (meaning they can move in all 4 directions just by turning the wheels in different directions) Here is a video of one of the industrial robots

My robot is different in costs (under $100 and in some cases under $50 depending on the robot cassie used) uses only 2 wheels, and can not move in all four directions without turning the whole body of the robot.
Turning the body of the robot was the biggest challenge of this project. “

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