2.7 Variable Resistor Servo Control System

In this project, we use a servo and a potentiometer to simulate a steering wheel. Rotating the potentiometer will drive the servo to turn together.

Component List

  • Raspberry Pi Pico W x1

  • MicroUSB cable x1

  • 830 Tie-Points Breadboard x1

  • Potentiometer x1

  • Servo x1

  • Jumper Wire Several

Circuit Configuration

../_images/Potentiometer_Servo_Wiring.png

  • Servo motor control signal interfaces with GPIO pin GP13.

  • Potentiometer analog output connects to GPIO pin GP26.

Programming Implementation

Note

  • Follow the visual programming guide below using drag-and-drop techniques.

  • Load 2.7_Potentiometer_Control_Servo.png from the directory Ultimate-Starter-Kit-for-Pico-W\Piper_Make. For comprehensive guidance, see Loading Existing Projects.

../_images/Potentiometer_Servo_Code.png

Upon Pico W connection, press the Start button to begin program execution. Adjust the potentiometer knob to control servo motor angular positioning in real-time.

How it Works?

../_images/Potentiometer_Servo_Code2.png

Set the rotation speed of pin15 (servo) to 15%.

  • [servo pin() set speed to ()%]: Used to set the rotation speed of the servo pin, the range is 0%~100%.

../_images/Potentiometer_Servo_Code3.png

Create a variable [angle], then read the voltage of A0. Use the [map value () from () to ()] block, map the voltage of A0 from 0 to 3.3V voltage range to 0 to 180°, and then use the mapped angle as the rotation angle of the servo.

  • [map value () from () to ()]: map a value from one range to another.

Note

The voltage of A0~A2 takes the range of 0~3.3V, even if your power supply is connected to VBUS (5V).