Hard⏱ time3 hr$ cost22

Ultrasonic Radar

A sweeping sensor maps nearby objects on a screen like a sonar display.

Result first

The build

Step 01

Fix the ultrasonic sensor on a sweeping servo.

Step 02

Code the servo to sweep while reading distance.

Step 03

Stream angle and distance to a computer.

Step 04

Plot the points as a live radar arc.

Working Principle

As the servo sweeps, the sensor measures distance at each angle; pairing angle with distance maps where objects sit around the robot.

The science behind it

It's polar mapping: combining a rotating sensor with echo timing recreates how real radar and sonar build a picture.

Take it further

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