Monitor Action Goal

R2026b

Monitor action goal in ROS 2 network

Since R2024a

• 

Monitor Action Goal ROS 2 block

To add a block to a model, double-click the canvas and start typing the block name. Then, select the block from the list.

Libraries:
ROS Toolbox / ROS 2

Description

The Monitor Action Goal block enables you to monitor the status, feedback and result of an active action goal in a ROS 2 network. This block accepts the UUID input as a Simulink^® non-virtual bus of unique_identifier_msgs/UUID message type.

To use this block, you must have a paired Send Action Goal block of a matching action name and type. Selections made in the Send Action Goal block are automatically synchronized with the Monitor Action Goal block.

You can use this block to monitor these states of the action goal after it is accepted by an action server.

Ports

Input

UUID — Unique ID dedicated to any goal message

non-virtual bus

Unique ID dedicated to any goal message, specified as a non-virtual bus of message type unique_identifier_msgs/UUID.

Data Types: bus

Output

StatusCode — Execution status of action goal corresponding to UUID input

scalar

Execution status of action goal corresponding to the UUID input, specified as an integer.

Status Code	Description
-1	The action server rejected the goal.
0	The action server accepted the goal but failed to set the status properly. This implies unknown status of the goal message.
1	The action server accepted the goal and is awaiting execution. This implies the accepted status of the goal message.
2	The action server accepted the goal and is currently in the process of execution. This implies the executing status of the accepted goal message.
3	The action server has accepted the cancel goal request initiated by the action client. This implies the canceling status of the accepted goal message.
4	The action server completed the goal successfully. This implies the succeeded status of the accepted goal message.
5	The action server canceled the goal based on an external request sent by the action client. This implies the canceled status of the accepted goal message.
6	The action server terminated the goal without an external request sent by the action client. This implies the aborted status of the accepted goal message.

Data Types: int8

Result — Result message associated with a particular action goal

non-virtual bus

Result message associated with a particular action goal, specified as a non-virtual bus.

Data Types: bus

Feedback — Feedback message associated with a particular action goal

non-virtual bus

Feedback message associated with a particular action goal, specified as a non-virtual bus.

• When a feedback message is available at a particular time step, the Feedback port outputs the latest feedback.

• When a feedback message is not available at a particular time step, the Feedback port outputs the last known feedback.

Dependencies

To enable this port, select the Show Feedback output port parameter.

Data Types: bus

ErrorCode — Error conditions while monitoring action goal

integer

Error conditions while monitoring an action goal, specified as an integer.

Error Code	Description
0	The action client sent the goal successfully and the action server accepted the goal.
1	The action client sent the goal but the action server rejected the goal.
2	The UUID input is invalid but the action server is available.
3	The action client failed to send the goal because the action server is not available.

Dependencies

To enable this port, select the Show ErrorCode output port parameter.

Data Types: uint8

Parameters

To edit block parameters interactively, use the Property Inspector. From the Simulink Toolstrip, on the Simulation tab, in the Prepare gallery, select Property Inspector.

Name — Action name inherited from paired Send Action Goal block

character vector

Action name inherited from paired Send Action Goal block, specified as a character vector.

Type — Action type inherited from paired Send Action Goal block

character vector

Action type inherited from paired Send Action Goal block, specified as a character vector.

Paired Send Action Goal Block — Path to paired Send Action Goal block

block path

Path to the Send Action Goal block paired with this Monitor Action Goal block. To create a paired Send Action Goal for the first time, select the Create paired Send Action Goal block parameter.

After you create a paired Send Action Goal block, clicking the path displays and highlights the Send Action Goal block in your model.

Tips

• For correct action client implementation, use only the Create paired Send Action Goal block parameter to create the Send Action Goal block associated with this Monitor Action Goal block. It is not recommended to add a Send Action Goal block from the library.

Show Feedback output port — Enable feedback output port

off (default) | on

Check this box to enable the Feedback output.

Show ErrorCode output port — Enable error code output port

off (default) | on

Check this box to enable the ErrorCode output. If an error condition occurs, the Result port outputs a blank message.

Programmatic Use: Add Block

To add the block programmatically, use the add_block function with one of these library block paths as the source.

"ros2lib/Monitor Action Goal"

Example: add_block("ros2lib/Monitor Action Goal","myModel/myBlock",MakeNameUnique="on")

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using Simulink® Coder™.

Usage notes and limitations:

The Monitor Action Goal block follows rate-based execution and not event-driven execution.

Version History

Introduced in R2024a