Color-based tracking in Drone Programming - Step-by-Step Execution

Concept Flow - Color-based tracking

Start Camera

↓

Capture Frame

↓

Detect Color Pixels

↓

Calculate Object Position

↓

Adjust Drone Movement

↓

Repeat or Stop

The drone camera captures frames, detects pixels of a target color, calculates the object's position, and moves accordingly in a loop.

Execution Sample

Drone Programming

frame = camera.capture()
color_mask = detect_color(frame, target_color)
position = find_object_position(color_mask)
drone.move_towards(position)

This code captures a frame, finds the target color pixels, calculates the object's position, and moves the drone toward it.

Execution Table

Step	Action	Input	Output	Drone Movement
1	Capture Frame	Camera active	Image frame with colors	Hover
2	Detect Color Pixels	Image frame, target_color=red	Mask highlighting red pixels	Hover
3	Calculate Object Position	Color mask	Coordinates (x=150, y=100)	Hover
4	Adjust Drone Movement	Coordinates (150,100)	Movement command: move right and forward	Moves right and forward
5	Capture Frame	Camera active	New image frame	Moves right and forward
6	Detect Color Pixels	New frame, target_color=red	Mask highlighting red pixels	Moves right and forward
7	Calculate Object Position	New color mask	Coordinates (x=160, y=110)	Moves right and forward
8	Adjust Drone Movement	Coordinates (160,110)	Movement command: move right and forward	Moves right and forward
9	Repeat or Stop	User input or condition	Continue tracking or stop	Continue or hover

💡 Tracking stops when user commands or target color is lost

Variable Tracker

Variable	Start	After Step 3	After Step 7	Final
frame	None	Image frame 1	Image frame 2	Image frame N
color_mask	None	Mask of red pixels 1	Mask of red pixels 2	Mask of red pixels N
position	None	(150, 100)	(160, 110)	(xN, yN)
drone_movement	Hover	Moves right and forward	Moves right and forward	Hover or move

Key Moments - 2 Insights

Why does the drone keep moving even if the color position changes slightly?

Because each new frame updates the position and the drone adjusts movement accordingly, as shown in steps 3, 4, 7, and 8 in the execution_table.

What happens if the target color is not detected in a frame?

The color_mask will be empty, so the position cannot be calculated, and the drone will hover or stop, as implied in the exit_note.

Visual Quiz - 3 Questions

Look at the execution_table at step 3, what is the position output?

A (150, 100)

B (160, 110)

C No position

D (0, 0)

💡 Hint

Check the 'Output' column at step 3 in the execution_table.

At which step does the drone first move right and forward?

A Step 2

B Step 1

C Step 4

D Step 9

💡 Hint

Look at the 'Drone Movement' column in the execution_table.

If the color_mask is empty, what will the drone most likely do?

A Move right

B Hover or stop

C Move forward

D Move backward

💡 Hint

Refer to the key_moments and exit_note about what happens when the target color is lost.

Concept Snapshot

Color-based tracking uses the drone camera to capture frames.
It detects pixels matching a target color.
Calculates the object's position from these pixels.
Drone moves toward the detected position.
This repeats continuously to follow the object.

Full Transcript

Color-based tracking works by the drone camera capturing images continuously. Each image is checked for pixels of a specific color. When these pixels are found, the program calculates where the object is in the frame. The drone then moves in the direction of the object to follow it. This process repeats, allowing the drone to track the colored object in real time. If the color is lost or the user stops the program, the drone will hover or stop moving.