stretch_tutorials/ros2/respeaker_mic_array.md

ReSpeaker Microphone Array

For this tutorial, we will get a high-level view of how to use Stretch's ReSpeaker Mic Array v2.0.

Stretch Body Package

In this section we will use command line tools in the Stretch_Body package, a low-level Python API for Stretch's hardware, to directly interact with the ReSpeaker.

Begin by typing the following command in a new terminal.

stretch_respeaker_test.py

The following will be displayed in your terminal:

For use with S T R E T C H (TM) RESEARCH EDITION from Hello Robot Inc.

* waiting for audio...
* recording 3 seconds
* done
* playing audio
* done

The ReSpeaker Mico Array will wait until it hears audio loud enough to trigger its recording feature. Stretch will record audio for 3 seconds and then replay it through its speakers. This command line is a good method to see if the hardware is working correctly.

To stop the python script, type Ctrl + c in the terminal.

ReSpeaker_ROS Package

A ROS package for the ReSpeaker is utilized for this section.

Begin by running the sample_respeaker.launch.py file in a terminal.

ros2 launch respeaker_ros2 respeaker.launch.py

This will bring up the necessary nodes that will allow the ReSpeaker to implement a voice and sound interface with the robot.

ReSpeaker Topics

Below are executables you can run to see the ReSpeaker results.

ros2 topic echo /sound_direction
ros2 topic echo /sound_localization
ros2 topic echo /is_speeching
ros2 topic echo /audio
ros2 topic echo /speech_audio
ros2 topic echo /speech_to_text

There's also another topic called /status_led, with this topic you can change the color of the LEDs in the ReSpeaker, you need to publish the desired color in the terminal using ros2 topic pub. We will explore this topics in the next tutorial.

You can also set various parameters via dynamic_reconfigure by running the following command in a new terminal.

ros2 run rqt_reconfigure rqt_reconfigure