Arduino Robot Line-Obstacle Fix

I’m working with a Keyestudio KS4070 4-wheel Bluetooth car that my daughter assembled, but the current sketch isn’t doing what it should. With its line-tracking module, ultrasonic range sensor, and infrared receiver all wired in and verified, the car still refuses to: • stay on the black line, • swerve around any obstacle in its path, and • pause precisely at programmed checkpoints. I need a clean, well-commented Arduino sketch delivered today that makes those three behaviours rock-solid. Please structure the code into clear functions for line detection, obstacle avoidance, and stop-point handling so future tweaks are easy. Serial-print debug messages are welcome but keep them toggle-able with a macro or flag. Acceptance criteria • Upload sketch, I flash it once, car continuously follows a 2 cm-wide black tape loop without drifting. • When an object is placed 15 cm ahead, vehicle brakes, turns, and rejoins the line smoothly. • It halts for exactly 2 seconds at each RFID-tagged or IR-marked stop (you can choose which of the existing sensors to use; just document it). Hand over the .ino file plus any calibration values or library references you use (e.g., Keyestudio_LineTracker, NewPing, IRremote). A quick note on wiring assumptions and a short read-me are appreciated. Speed is critical, so if you’re confident you can meet the deadline, let’s get started right away.

Project ID: 40442576