ROS Transport¶
Note
Many file names and identifiers in this API contain placeholders for event, monitor, and synchronous set names. These placeholders are marked by the use of ALLCAPS.
This asynchronous transport sends asynchronous events using ROS topics. Each
synchronous set becomes a ROS node. The output from mgen in this case is a
ROS package containing all the nodes in the monitoring system. Use the -d
option for mgen to provide the path to your workspace’s src/ directory.
PEDL Events Under ROS¶
The ROS transport was designed under the assumption that PEDL events would
generally be asynchronous, so they could come from or be sent to the rest of
the system via ROS topics. Accordingly, architecture specifications for ROS
will likely want to avoid using the pedl, imported, or exported
keywords in synchronous set definitions.
By default, code for a PEDL node is still generated, but it is disabled in the
CMakeLists.txt and SYSNAME.launch files.
Message/Topic Configuration¶
By default, SMEDL generates a message definition for each imported PEDL event and each exported monitor event and creates a new topic for each one. This is all configurable, allowing existing ROS topics to be used as the source for PEDL events and the destination for exported monitor events.
All of this configuration resides in SYSNAME_ros_config.inc, a special C++
source code file that gets included in each node. This file contains
instructions for changing the message type and topic for a particular event, as
well as the message fields used to represent each source event parameter and
each source monitor identity.
The type of each field used as an event parameter or monitor identity should match the appropriate SMEDL type:
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ROS Type |
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