5.2.2 Screen Control

The screen control interface provides full display control capabilities, including emoji playback, video playback, and more. It enables developers to implement rich visual interaction features for the robot.

Key Features

• Playback of multiple preset emoji expressions

• Custom video playback

• Playlists (coming soon) and loop playback

• Playback priority control

Emoji Playback Status Topic

Topic Name	Data Type	Description	QoS	Frequency
/face_ui_proxy/status	FaceEmojiStatus	Emoji playback status	RELIABLE	1Hz

• FaceEmojiStatus ros2-msg @ face_ui/FaceEmojiStatus.msg

  # Emoji Status Info
  
  MessageHeader header             # Message header
  string e_path                    # Path of the emoji file
  string[] e_path_list             # List of emoji paths in the current sequence
  uint8 e_id                       # Emoji ID
  uint8 mode                       # Playback mode (1: once, 2: loop)
  int32 priority                   # Priority
  uint8 status                     # Current status (0: idle, 1: start, 2: running, 3: completed, 4: stopped)
  float64 time_to_end_ms           # Remaining time (seconds)
  

  status special notes:

  • The following states are edge-triggered (reported only once):

    • 1 - start, 3 - completed, 4 - stopped

Emoji Playback Service

Service Name	Data Type	Description
/aimdk_5Fmsgs/srv/PlayEmoji	PlayEmoji	Play emoji

• PlayEmoji ros2-srv @ face_ui/srv/PlayEmoji.srv

  # Play Emoji
  # Service: /aimdk_5Fmsgs/srv/PlayEmoji
  
  # Request
  CommonRequest header  # Request header
  
  uint8 emotion_id  # Emoji ID
  uint8 mode  # Playback mode (1: once, 2: loop)
  int32 priority  # Playback priority
  
  ---
  
  # Response
  CommonResponse header  # Response header
  
  bool success  # Whether the command succeeded
  string message
  

  emotion_id Emoji Mapping Table:

  Emoji ID	Emoji name	Description
  1	Blink	Basic blink action
  10	Calm - eye variation 1	Eye variation for calm state
  11	Calm - eye variation 2	Eye variation for calm state
  20	Calm - game	Game-state emoji
  30-33	Calm - cute	Cute expression series
  40	Close eyes	Close-eye action
  50	Open eyes	Open-eye action
  60	Bored	Bored expression
  70	Abnormal	Abnormal state
  80	Sleeping	Sleeping state
  90	Happy	Happy expression
  100-101	Extra happy / ecstatic	Extremely happy expression
  110	Sad	Sad expression
  120	Sympathy	Sympathetic expression
  130	Confused	Confused expression
  140	Shocked	Shocked expression
  150	Acting cute	Cute/affectionate expression
  160	Serious	Serious expression
  170	Thinking	Thinking expression
  180	Angry	Angry expression
  190	Extra angry	Extremely angry expression
  200	Adoration	Adoring expression
  210	Extra adoring	Extremely adoring expression
  220	Charging	Charging state

  priority Priority Mechanism Explanation:

  • This priority mechanism applies to emoji playback (PlayEmoji) and video playback (PlayVideo).

  • If the new request’s priority is not lower than the current one, it overrides the current request.

  • If the new request’s priority is lower, it is ignored.

Video Playback Service

Service Name	Data Type	Description
/aimdk_5Fmsgs/srv/PlayVideo	PlayVideo	Play video

• PlayVideo ros2-srv @ face_ui/srv/PlayVideo.srv

  # Play Video
  # Service: /aimdk_5Fmsgs/srv/PlayVideo
  
  # Request
  CommonRequest header             # Request header
  string video_path                # Absolute path of video file (must be on the interaction compute unit and readable by all)
  uint8 mode                       # Playback mode (1: once, 2: loop)
  int32 priority                   # Playback priority
  
  # Response
  CommonResponse header            # Response header
  bool success                     # Whether playback succeeded
  string message                   # Response message
  

  Notes:

  • By default, video playback does not include audio.

  • Audio and video files must use absolute paths.

  • Audio and video files must be stored on the interaction compute unit (PC3, 10.0.1.42), not the development compute unit (PC2).

  • Audio and video files (and all parent directories up to root) must be readable by all users(new subdirectory under /var/tmp/ is recommended)

Programming Examples

For detailed code examples and explanations, refer to:

• C++ Examples:

  • Emoji Control

  • Play Video

• Python Examples:

  • Emoji (expression) control

  • Play video

Safety Notes

Warning

Display Control Limitations

• Emoji playback occupies display resources; manage resources carefully.

• Video playback requires correct and accessible file paths.

• Set priorities properly to avoid conflicts.

Caution

As standard ROS DO NOT handle cross-host service (request-response) well, please refer to SDK examples to use open interfaces in a robust way (with protection mechanisms e.g. exception safety and retransmission)

Note

Best Practices

• Use appropriate playback modes to avoid unnecessary looping.

• Monitor display states and handle exceptions.

• Implement content queueing for better control.

• Ensure correct file paths and formats.