2.11 Reversing System

For this project we used an ultrasonic module and an active buzzer to create a reversing alarm system. The ultrasonic module is used to detect the distance, and the buzzer emits different frequencies of alarm sounds depending on the distance.

Bill of Materials

In this project, we need the following components.

It’s definitely convenient to buy a whole kit, here’s the link:

Name

ITEMS IN THIS KIT

LINK

Kepler Kit

450+

Kepler Kit

You can also buy them separately from the links below.

SN

COMPONENT

QUANTITY

LINK

1

Raspberry Pi Pico W

1

BUY

2

Micro USB Cable

1

3

Breadboard

1

BUY

4

Wires

Several

BUY

5

Transistor

1(S8050)

BUY

6

Resistor

1(1KΩ)

BUY

7

Active Buzzer

1

8

Ultrasonic Sensor Module

1

BUY

Wiring

reversing_system0

  • The Echo and Trig pins of the ultrasonic module are connected to GP15 at the same time, so that the ultrasonic module sends and receives signals from GP15.

  • The middle pin of the transistor connected to the buzzer is connected to GP14 through a 1kΩ resistor.

Code

Note

  • You can refer to the image below to write code by dragging and dropping.

  • Import 2.11_reversing_system.png from the path of kepler-kit-main\piper. For detailed tutorials, please refer to Import the Code.

reversing_system

  • After connecting Pico W, click the Start button and the code starts to run.

  • When the ultrasonic detection distance is less than 5cm, the buzzer emits a sharp sound (0.1s).

  • When the detection distance is between 5~10cm, the buzzer emits a slightly slow sound (0.5s).

  • When the detection distance is greater than 10cm, there is a sound prompt every 1 second.

How it Works?

reversing_system1

Read the distance (in cm) of the ultrasonic detection, and store it in the variable [distance].

reversing_system2

When distance is less than or equal to 5, set the variable intervals to 0.1s. The variable [intervals] is the interval between buzzer sounds.

reversing_system3

When distance is greater than 5 and less than or equal to 10, set the [intervals] to 0.5s.

reversing_system4

When distance is greater than 10, set the [intervals] time to 1s.

reversing_system5

Finally, make the buzzer sound every [intervals] seconds.