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Sensors Tutorial

This tutorial covers how to work with Stretch's various sensors including the ReSpeaker microphone array, IMU, bump sensors, and cliff sensors.

ReSpeaker Microphone Array

Stretch comes equipped with a ReSpeaker Mic Array v2.0 that provides audio input capabilities.

Basic ReSpeaker Usage

To start using the ReSpeaker microphone array, launch the ReSpeaker node:

ros2 launch respeaker_ros2 respeaker.launch.py

This will start publishing audio data and speech recognition results to various topics.

Available Topics

The ReSpeaker publishes to several topics:

  • /audio - Raw audio data
  • /speech_to_text - Recognized speech text
  • /sound_direction - Direction of detected sound
  • /is_speeching - Boolean indicating if speech is detected

For detailed information about ReSpeaker topics, see the ReSpeaker Topics tutorial.

IMU Sensor

Stretch includes an IMU (Inertial Measurement Unit) that provides orientation and motion data.

Accessing IMU Data

The IMU data is published to the /stretch/imu topic as sensor_msgs/Imu messages.

ros2 topic echo /stretch/imu

Bump Sensors

Stretch has bump sensors that detect physical contact with obstacles.

Cliff Sensors

Cliff sensors help prevent Stretch from falling off edges or down stairs.

Sensors Examples