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Version: QTrobot V3

Face and Emotion

The /qtrobot/face/... services control QTrobot's animated face — playing emotions and moving its gaze. These examples assume the gateway from Connection is already running.

List available emotions​

ros2 service call /qtrobot/face/emotion/list qtrobot_interfaces/srv/FaceEmotionList "{}"

Show an emotion​

#!/usr/bin/env python3
import rclpy
from rclpy.node import Node
from qtrobot_interfaces.srv import FaceEmotionShow, FaceEmotionStop


class FaceClient(Node):
    def __init__(self):
        super().__init__('face_client')
        self.show_client = self.create_client(FaceEmotionShow, '/qtrobot/face/emotion/show')
        self.stop_client = self.create_client(FaceEmotionStop, '/qtrobot/face/emotion/stop')
        self.show_client.wait_for_service(timeout_sec=5.0)

    def show(self, emotion: str, speed: float = 1.0):
        future = self.show_client.call_async(FaceEmotionShow.Request(emotion=emotion, speed=speed))
        rclpy.spin_until_future_complete(self, future)
        return future.result()

    def stop(self):
        future = self.stop_client.call_async(FaceEmotionStop.Request())
        rclpy.spin_until_future_complete(self, future)
        return future.result()


def main():
    rclpy.init()
    node = FaceClient()
    node.show('QT/happy')
    node.destroy_node()
    rclpy.shutdown()


if __name__ == '__main__':
    main()

Emotion names follow the <group>/<name> pattern returned by /qtrobot/face/emotion/list, such as QT/happy or QT/sad.

Stop an emotion​

ros2 service call /qtrobot/face/emotion/stop qtrobot_interfaces/srv/FaceEmotionStop "{}"

Look at a point​

ros2 service call /qtrobot/face/look qtrobot_interfaces/srv/FaceLook \
    "{l_eye: '[0.2, 0.1]', r_eye: '[0.2, 0.1]', duration: 1.0}"

l_eye/r_eye are JSON-encoded [x, y] normalized gaze targets, and duration is how long the movement should take, in seconds.

Next steps​

Continue with the Gesture tutorial, or see the full face namespace in the ROS2 API Reference.