Note: This tutorial assumes that you have completed the previous tutorials: Basics.
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Communication Handler

Description: Details on the Communication Handler Node

Keywords: qbrobotics SoftHand qbmove control

Tutorial Level: BEGINNER

Next Tutorial: Control

The Communication Handler Node has no parameters to be set, therefore it is always launched like this:

roslaunch qb_device_driver communication_handler.launch

On start, it scans the serial communication resources connected to you system and shows a list of the devices it has found. By default it never scans again for new devices, apart from asking it explicitly during the initialization of a control Node.

This is a simple example when starting the Communication Handler with two qbroboticsĀ® devices connected on two distinct USB ports:

[ INFO] [1524044523.511369300]: [CommunicationHandler] handles [/dev/ttyUSB1].
[ INFO] [1524044524.426984697]: [CommunicationHandler] handles [/dev/ttyUSB0].
[ INFO] [1524044525.218613760]: [CommunicationHandler] has found [2] devices connected:
[ INFO] [1524044525.218696997]:                        - device [1] connected through [/dev/ttyUSB0]
[ INFO] [1524044525.218736612]:                        - device [2] connected through [/dev/ttyUSB1]

When the Communication Handler is on, it provides all the Services required to interact with the connected devices: e.g. get info or measurements, activate or deactivate motors, set commands, and even more... A detailed description of the services can be found in the qb_device_driver package wiki.

Wiki: qb_device_control/Tutorials/Communication Handler (last edited 2018-06-04 11:01:11 by AlessandroTondo)