Servo Component

The servo component allows you to use servo motors with ESPHome. Servos are motor controllers that contain all the electronics necessary for driving the motor and provide a simple PWM interface to control the motor.

This component works with both continuous-rotation and absolute servos and has a similar interface to the Arduino Servo library.

First, create an output component (here esp8266_pwm) for the pin the servo is connected to. Then connect that output to the servo component by assigning an ID. Please note the frequency of the output should be around 50Hz, as most servo controllers only operate in this frequency range.

Note

This component will not show up in the Home Assistant front-end automatically because Home Assistant doesn’t have support for servos. Please see Home Assistant Configuration.

# Example configuration entry
servo:
  - id: my_servo
    output: pwm_output

# Example output platform
# On ESP32, use ledc output
output:
  - platform: esp8266_pwm
    id: pwm_output
    pin: GPIOXX
    frequency: 50 Hz

Configuration variables:

  • output (Required, ID): The ID of the output component to use for this servo.

  • id (Required, ID): The ID of this servo so that it can be controlled.

Advanced Options:

  • min_level (Optional, percentage): The PWM duty cycle the minimum value (-100%) will map to. Defaults to 3%.

  • idle_level (Optional, percentage): The PWM duty cycle the idle value (0%) will map to. This is also the state of the servo at startup. Defaults to 7.5%.

  • max_level (Optional, percentage): The PWM duty cycle the maximum value (100%) will map to. Defaults to 12.0%.

  • restore (Optional, boolean): Whether to restore the state of the servo motor at startup. This is useful if you have an absolute servo motor and it goes back to its 0 position at startup. Defaults to false.

  • auto_detach_time (Optional, Time): The time after reaching the target value when the servo will be detached`, if set to zero, servo will not be detached. Defaults to 0s.

  • transition_length (Optional, Time): The time needed for a full movement (-1.0 to 1.0). This will effectively limit the speed of the servo, the larger the value, the slowest the servo will move. Defaults to 0s. This can slow down the servo to avoid loud noises or just make the movement not jerking.

Note

Some servos support a larger range for the level. For continuous rotation servos this can speed them up a bit and for absolute servos this can extend their angle range. You can configure the min_level and max_level options to adjust the level range to match your servo (Experiment with these values).

servo.write Action

To use your servo motor in automations or templates, you can use this action to set the target level of the servo from -100% to 100%.

  • -100% (= -1.0) is the minimum value of the servo. For continuous-rotation servos this will rotate the servo backward.

  • 0% (= 0.0) is the idle level of the servo. For continuous-rotation servos this will stop the servo.

  • 100% (= 1.0) is the maximum value of the servo. For continuous-rotation servos this will rotate the servo forward.

on_...:
  then:
  - servo.write:
      id: my_servo
      level: -100.0%

  # Templated
  - servo.write:
      id: my_servo
      # For template values, range is [-1; 1]
      level: !lambda |-
        if (id(my_binary_sensor).state) {
          return 1.0;
        } else {
          return -1.0;
        }

Configuration options:

  • id (Required, ID): The ID of the servo.

  • level (Optional, percentage, templatable): The target level. Range is from -100% to 100% (-1.0 to 1.0).

Note

This action can also be expressed as a lambda:

id(my_servo).write(1.0);

servo.detach Action

This Action allows you to disable the output on a servo motor - this will make the servo motor stop immediately and disable its active control.

on_...:
  then:
  - servo.detach: my_servo

Note

This action can also be expressed as a lambda:

id(my_servo).detach();

Home Assistant Configuration

The easiest way to control your servo from Home Assistant is to add a number to your ESPHome configuration. See Number for more information.

number:
  - platform: template
    name: Servo Control
    min_value: -100
    initial_value: 0
    max_value: 100
    step: 1
    optimistic: true
    set_action:
      then:
        - servo.write:
            id: my_servo
            level: !lambda 'return x / 100.0;'

servo:
  - platform: ...
    # [...] servo config
    id: my_servo

See Also