std_msgs

std_msgs provides many basic message types. Only a few messages are intended for incorporation into higher-level messages. The primitive and primitive array types should generally not be relied upon for long-term use.

For more information about ROS 2 interfaces, see docs.ros.org.

Messages (.msg)

• ColorRGBA: A single RGBA value for representing colors.
• Empty: Does not hold any information, useful when the sending of a message would provide sufficient information.
• Header: Standard metadata for higher-level stamped data types used to communicate timestamped data in a particular coordinate frame.

Primitive Types

std_msgs provides the following wrappers for ROS primitive types, which are documented in the msg specification. It also contains the Empty type, which is useful for sending an empty signal. However, these types do not convey semantic meaning about their contents: every message simply has a field called “data”. Therefore, while the messages in this package can be useful for quick prototyping, they are NOT intended for “long-term” usage. For ease of documentation and collaboration, we recommend that existing messages be used, or new messages created, that provide meaningful field name(s).

• Bool
• Byte
• Char
• Float32
• Float64
• Int8
• Int16
• Int32
• Int64
• String
• UInt8
• UInt16
• UInt32
• UInt64

Array Types

std_msgs also provides the following “MultiArray” types, which can be useful for storing sensor data. However, the same caveat as above applies: it’s usually “better” (in the sense of making the code easier to understand, etc.) when developers use or create non-generic message types (see discussion in this thread for more detail).

• ByteMultiArray
• Float32MultiArray
• Float64MultiArray
• Int8MultiArray
• Int16MultiArray
• Int32MultiArray
• Int64MultiArray
• MultiArrayDimension
• MultiArrayLayout
• UInt16MultiArray
• UInt32MultiArray
• UInt64MultiArray
• UInt8MultiArray

Quality Declaration

This package claims to be in the Quality Level 1 category, see the Quality Declaration for more details.

Changelog for package std_msgs

5.6.0 (2025-04-25)

5.5.0 (2025-03-20)

5.4.2 (2024-11-20)

5.4.1 (2024-06-17)

5.4.0 (2024-04-26)

• Update quality declaration documents (#245)
• Contributors: Christophe Bedard

5.3.4 (2024-04-16)

5.3.3 (2024-04-10)

5.3.2 (2024-04-10)

• Clarify the license. (#241) In particular, every package in this repository is Apache 2.0 licensed except for sensor_msgs_py. So move the CONTRIBUTING.md and LICENSE files down into the individual packages, and make sure that sensor_msgs_py has the correct CONTRIBUTING.md file (it already had the correct LICENSE file).
• Contributors: Chris Lalancette

5.3.1 (2024-03-28)

5.3.0 (2024-01-24)

5.2.2 (2023-12-26)

5.2.1 (2023-11-06)

5.2.0 (2023-06-07)

5.1.0 (2023-04-27)

5.0.0 (2023-04-11)

4.7.0 (2023-02-13)

• Update common_interfaces to C++17. (#215)
• [rolling] Update maintainers - 2022-11-07 (#210)
• Contributors: Audrow Nash, Chris Lalancette

4.6.1 (2022-11-02)

4.6.0 (2022-09-13)

4.5.0 (2022-05-19)

4.4.0 (2022-04-29)

4.3.0 (2022-04-29)

4.2.1 (2022-03-31)

4.2.0 (2022-03-30)

4.1.1 (2022-03-26)

4.1.0 (2022-03-01)

• Interface packages should fully <depend> on the interface packages that they depend on (#173)
• Contributors: Grey

4.0.0 (2021-12-14)

• Update maintainers to Geoffrey Biggs and Tully Foote (#163)
• Contributors: Audrow Nash

3.0.0 (2021-08-24)

2.3.0 (2021-08-11)

2.2.3 (2021-04-27)

2.2.2 (2021-04-06)

• Change index.ros.org -> docs.ros.org. (#149)
• updating quality declaration links (re: ros2/docs.ros2.org#52) (#145) Co-authored-by: Simon Honigmann <<shonigmann@blueorigin.com>>
• Contributors: Chris Lalancette, shonigmann

2.2.1 (2021-01-25)

2.2.0 (2020-12-10)

• Update QDs to QL 1 (#135)
• Update package maintainers. (#132)
• Updated Quality Level to 2 (#131)
• Contributors: Alejandro Hernández Cordero, Michel Hidalgo, Stephen Brawner

2.1.0 (2020-07-21)

2.0.2 (2020-07-21)

• Update Quality levels to level 3 (#124)
• Add Security Vulnerability Policy pointing to REP-2006. (#120)
• Contributors: Chris Lalancette, brawner

2.0.1 (2020-05-26)

• QD Update Version Stability to stable version (#121)
• Contributors: Alejandro Hernández Cordero

1.0.0 (2020-05-20)

• Add deprecation messages to all messages now in example_interfaces (#116)
• Add current-level quality declarations (#109)
• Contributors: Tully Foote, brawner