Line Jumping Robot with color detection

A line-following robot with a twist: it can "jump" between separate tracks based on colored markers it spots along the way. Red says go left, blue says go right.

The track

The robot follows 3 cm-thick black tracks pasted on a white background. Scattered beside those tracks are small patches of red or blue — the switching cues that tell it when, and where, to change lanes.

How it works

As it follows a line, the robot continuously scans the area beside the track for color. When it spots a colored patch it changes tracks: a red patch means jump to the left track, and a blue patch means jump to the right.

The custom color sensor

Rather than an off-the-shelf module, the color detection uses a hand-built sensor made from an RGB LED and an LDR (light-dependent resistor). The RGB LED lights the surface one color channel at a time while the LDR reads the reflected intensity of each channel — from those readings the robot works out whether it's looking at red, blue, or plain background.

Build at a glance

• Line following: reflectance sensing over 3 cm black-on-white tracks.

• Color sensing: a custom RGB-LED + LDR sensor reading red / green / blue reflectance.

• Decision: red patch → switch to the left track, blue patch → switch to the right.