component.controller.CommunicationController

The CommunicationController component can be used to send data from a simulation to another using ZMQ library. To use this component you need to compile SOFA with the option SOFTROBOTS_COMMUNICATIONCONTROLLER enabled in cmake, and install the ZMQ library:

1.1- On Linux

#Debian/Ubuntu

sudo apt-get install libzmq3-dev

#Fedora

sudo dnf install zeromq-devel

1.1- On MacOS (missing)

1.1- On Windows, download the Windows source of libzmq and build using Visual Studio. Put a copy of zmq.hpp from the cppzmq project (github) in the include folder of libzmq.

2- In the cmake gui, enable: SOFTROBOTS_COMMUNICATIONCONTROLLER = true

3- Compile SOFA

In this directory (“SoftRobots/examples/component/controller/CommunicationController”) you will find one example showing how to use the component:

• SimulationDirect_Receiver.py : Soft actuated accordion, direct problem
• SimulationInverse_Sender.py : Soft actuated accordion, inverse problem

Below is a video of the simulations running simultaneously and with a communication between them.

Example

SimulationDirect_Receiver.py:

#For local communication
accordion.addObject('CommunicationController', name="sub", listening='1',
                                                 job="receiver", port="5558", nbDataField="4", pattern="0")
#Between two different computers, specify the ip adress of the sender
#accordion.addObject('CommunicationController', name="sub", listening='1',
                                                 job="receiver", port="5558", nbDataField="4", ip="...")

SimulationInverse_Sender.py:

accordion.addObject('CommunicationController', listening='1', job="sender", port="5558",                                        nbDataField="4", pattern="0",
                        data1="@cavity/pressure.volumeGrowth",
                        data2="@cables/cable1.displacement",
                        data3="@cables/cable2.displacement",
                        data4="@cables/cable3.displacement")

Data fields

Required	Description
job	If unspecified, the default value is sender.
pattern	Pattern used for communication. publish/subscribe: Messages sent are distributed in a fan out fashion to all connected peers. Never blocks. request/reply: Message sent are waiting for reply. Allows only an alternating sequence of send/reply calls. Default is publish/subscribe. WARNING: the pattern should be the same for both sender and receiver to be effective.
nbDataField	Number of field ‘data’ the user want to send or receive. Default value is 1.
data	Data to send or receive.
port	Default value 5556.

Optional	Description
HWM	If publisher, you can define the High Water Mark which is a hard limit on the maximum number of outstanding messages shall queue in memory. Default 0 (means no limit).
ip	IP adress of the sender. No given adress will set up a local communication.
atBeginAnimationStep	If true, will send or receive datas at begin of the animation step (if false, at end of the animation step). Default true.
beginAt	Time step value to start the communication at.
timeOut	Set time out (in ms) before killing the communication. Default is 3000ms, 0 means no time out.