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eeros_architecture:hal:config_ros

Configuration File for ROS

As described in Using ROS through EEROS HAL you can directly map EEROS signal onto ROS messages through the EEROS HAL. The wrapper library EEROS-ROS is used to connect the EEROS HAL with ROS topics.
The EEROS HAL digital and analog inputs and outputs can be defined as usual in a JSON file. In this file you specify into which message type these signals get packed. There are hundreds of different message types in ROS and it is possible to create custom types. For this reason, we currently support only a few by default. If one wishes to use other message types, the wrapper library can easily be extended.

The keywords for the EEROS-ROS wrapper library must be set as follows:

Keyword Type Remarks
library string libroseeros.so (include version e.g. *.so.0.1.2)
devHandle string e.g. testNodeHAL, this is the name of the node created by the HAL
type string e.g. AnalogIn / AnalogOut / DigIn / DigOut
additionalArguments string see table below

Additional Arguments

The additionalArguments are special arguments containing additional information about the communication with a ROS network. The next table shows all currently available arguments. topic and msgType are mandatory.

Keyword Type Remarks
topic string topic to listen or subscribe
msgType string message type
dataField string data member of message
callOne boolean newest availabe message is fetched (false), oldest not yet read message is fetched (true)
queueSize int size of buffer, default = 1000
useEerosSystemTime boolean use system time or timestamp of message

An example for an additional argument could be:

  "additionalArguments": "topic=/testNode/TestTopic3; msgType=sensor_msgs::LaserScan; dataField=scan_time; callOne=false; queueSize=100"

Implemented Message Types

The table below shows all currently implemented message types and associated data fields. If your desired message type is not implemented yet, you can easily implement it yourself, see below.

type msgType dataField
AnalogIn std_msgs::Float64 -
sensor_msgs::LaserScan angle_min
angle_max
angle_increment
time_increment
scan_time
range_min
range_max
AnalogOut std_msgs::Float64 -
sensor_msgs::LaserScan angle_min
angle_max
angle_increment
time_increment
scan_time
range_min
range_max
DigIn std_msgs::BatteryState present
DigOut std_msgs::BatteryState present

You can find a complete example, including a *.json file, in the Tutorials.

eeros_architecture/hal/config_ros.txt · Last modified: 2018/01/18 15:54 (external edit)