Using servos and stepper motors with Arduino

When working with robotics and automation using Arduino, one of the most important elements to consider are servos and stepper motors. These devices are essential for moving parts of a robot or performing automated tasks. In this context, let's explore how to use servos and stepper motors with Arduino, from basic connection to advanced programming.

Servants

The servo is a type of motor that can be positioned at any angle from 0 to 180 degrees. It is commonly used in robots to control the movement of arms, legs or heads. The main advantage of a servo is that it can be precisely controlled, which is essential for many robotics applications.

Connecting a servo to Arduino

To connect a servo to Arduino, you will need three connections: power (VCC), ground (GND) and signal (SIG). VCC is usually connected to the Arduino 5V pin, GND to the GND pin and SIG to any digital pin. It is important to note that some servos may require a 6V supply, so check your servo's specifications before connecting.

Programming a servo with Arduino

The Arduino Servo library makes it easy to program servos. First, you need to include the library at the top of your sketch:

#include 

Next, you need to create a Servo object:

Servo myServo;

In the setup() function, you need to attach the servo to the pin where it is connected:

myServo.attach(9);

In the loop() function, you can use the write() function to move the servo to a specific angle:

myServo.write(90);

Step motors

Step motors are another type of motor commonly used in robotics and automation. They are able to rotate in discrete steps, which allows for precise movement control. They are often used in 3D printers, CNC machines and other applications where precise movement is required.

Connecting a stepper motor to Arduino

Connecting a stepper motor to the Arduino is a bit more complex than connecting a servo. This is because stepper motors usually have four or more wires, each controlling a different coil inside the motor. To control a stepper motor, you will need a stepper motor driver, which is a device that controls the current sent to each coil.

The most common stepper motor drivers for the Arduino are the A4988 and the DRV8825. These drivers have four connections for the stepper motor (A1, A2, B1, B2), two connections for the Arduino (STEP and DIR), and two connections for the power supply (VMOT and GND).

Programming a stepper motor with Arduino

The Arduino Stepper library makes it easy to program stepper motors. First, you need to include the library at the top of your sketch:

#include 

Next, you need to create a Stepper object, specifying the number of steps per revolution and the pins connected to the stepper motor driver:

Stepper myStepper(200, 8, 9);

In the setup() function, you can set the motor speed using the setSpeed() function:

myStepper.setSpeed(60);

In the loop() function, you can use the step() function to move the motor a specific number of steps:

myStepper.step(100);

In summary, servos and stepper motors are essential components in robotics and automation with Arduino. They allow you to precisely control the movement of your creations, whether moving a robot arm, positioning a 3D print head, or turning a gear on an automated machine. With practice and experimentation, you can learn to control these engines with confidence and use them to create amazing designs.

Next page of the Free Ebook:

11Building a simple robot with Arduino

3 minutes