User Interface
The Create® 3 robot can interact with the user through its buttons and its light ring.
Responding to button presses
Whenever a button on the Create® 3 robot is pressed, its information will be published on the interface_buttons topic.
By subscribing to this topic, you will be able to detect when to start your custom policies.
Changing the light ring colors
Attention
The Create® 3 robot uses its light ring to notify the user about critical events. If you override its color, you may not notice these events.
You can change the color of the light ring on your Create® 3 robot by publishing a corresponding message on the cmd_lightring topic.
ros2 topic pub /cmd_lightring irobot_create_msgs/msg/LightringLeds "{override_system: true, leds: [{red: 255, green: 0, blue: 0}, {red: 0, green: 255, blue: 0}, {red: 0, green: 0, blue: 255}, {red: 255, green: 255, blue: 0}, {red: 255, green: 0, blue: 255}, {red: 0, green: 255, blue: 255}]}"
The easiest way to return lights to the default color (and relinquish their control to the robot) is to publish an empty message on the topic.
ros2 topic pub /cmd_lightring irobot_create_msgs/msg/LightringLeds "{}"
Additionally, an action server named led_animation can take Blink or Spin animation goals to execute a pattern for a fixed duration.
See LedAnimation.action.
For example you can run the following:
ros2 action send_goal led_animation irobot_create_msgs/action/LedAnimation "{animation_type: 1, lightring: {leds: [{red: 255, green: 0, blue: 0}, {red: 0, green: 255, blue: 0}, {red: 0, green: 0, blue: 255}, {red: 255, green: 255, blue: 0}, {red: 255, green: 0, blue: 255}, {red: 0, green: 255, blue: 255}], override_system: true},max_runtime: {sec: 500, nanosec: 0}}"
Playing sound through the speakers
You can play sound out of your Create® 3 robot speakers by publishing a corresponding message on the cmd_audio topic.
Important
A best-effort publisher will not be able to communicate with this subscription as of G.4.4 / H.1.1 as its QOS has been changed to reliable from best-effort. See this compatibilty matrix for details.
ros2 topic pub --once /cmd_audio irobot_create_msgs/msg/AudioNoteVector "{append: false, notes: [{frequency: 100, max_runtime: {sec: 1,nanosec: 0}}, {frequency: 50, max_runtime: {sec: 1,nanosec: 0}}]}"
This example command will play 2 notes at the given frequencies back to back with the given 1 second length for each note.
append is used to dictate the policy if an audio sequence is already playing when a new value comes in on the topic.
append: truetells the sound manager to play this audio sequence after the current sequence finishes playing.append: falsetell the sound manager to override any currently playing sequence with the new sequence.
Publishing an empty notes vector with append: false will stop any currently playing audio sequences.
Additionally, an action server named audio_note_sequence can take an AudioNoteVector and a number of iterations to play it.
See AudioNoteSequence.action.
The action goal will succeed when the sequence has finished playing so you can coordinate audio runtime with other actions. If you set iterations to -1, it will play until it is canceled.
For example you can run the following:
ros2 action send_goal /audio_note_sequence irobot_create_msgs/action/AudioNoteSequence "{iterations: 3,note_sequence:{append: false, notes: [{frequency: 100, max_runtime: {sec: 1,nanosec: 0}}, {frequency: 50, max_runtime: {sec: 1,nanosec: 0}}]}}"