Sensor Digital

Line Tracking Sensor Module

A KY-033 line tracking module compares reflected infrared light from light and dark surfaces.

Part images

KY-033 Module Photo. Module Photo for the KY-033 Line Tracking Sensor Module. Image source: Joy-IT SensorKit KY-033 module documentation
KY-033 Pinout / Module Diagram. Pinout / Module Diagram for the KY-033 Line Tracking Sensor Module. Image source: Joy-IT SensorKit KY-033 module documentation
KY-033 Arduino Wiring Diagram. Arduino Wiring Diagram for the KY-033 Line Tracking Sensor Module. Image source: Joy-IT SensorKit KY-033 module documentation
KY-033 Raspberry Pi Wiring Diagram. Raspberry Pi Wiring Diagram for the KY-033 Line Tracking Sensor Module. Image source: Joy-IT SensorKit KY-033 module documentation

What it is

A KY-033 line tracking module compares reflected infrared light from light and dark surfaces.

How students use it

Students use it for line-following robot ideas, edge detection, counters, and contrast experiments.

Pins and power

Signal output, VCC, and GND on typical KY-033 boards.

Use module power and output levels that are safe for Pico GPIO.

The output changes when surface reflectivity crosses the module threshold.

Voltage and safety

Confirm output voltage before connecting to Pico.

Educational sensing only; do not use as a safety boundary detector.

Module internals

Main component: Reflective IR sensor pair with comparator circuitry.

IR emitter, receiver, comparator, indicator LED, trimmer/resistors, PCB, and header.

Datasheet notes

Detection depends on surface color, distance, lighting, and sensor angle.

Common libraries

Use machine.Pin for the digital output.

Common mistakes

Mounting too high, testing on glossy surfaces, using it in direct sunlight, and expecting precise distance readings.