[ros-users] ros node protocol

Andrew Harris andrew.unit at gmail.com
Sat May 22 12:59:39 UTC 2010

Hi -

   I'm interested in implementing a client library in language X.
I've read the below "Implementing Client Libraries" page, and it's
quite informative.  I know that a ros node has to have an XMLRPC
server running as well as an additional TCP socket to handle incoming
topic connection requests and that the node also has to support a
commandline API.  The thing I am not so sure about is all of the
marshalling and demarshalling stuff that is created automatically for,
for example, the rospy client.  I define my new messages in a YAML
file and there is some magic that creates python functions to do the
marshalling and demarshalling.  That implies that I must also write
functions in some language (not necessarily language X) that reads
YAML files and outputs marshalling and demarshalling routines in
language X?  And it has to integrate with cmake?  This is the part
that I am not so sure about.


On Sun, Jan 10, 2010 at 1:19 AM, Ken Conley <kwc at willowgarage.com> wrote:
> The best I can offer right now is this page:
> http://www.ros.org/wiki/Implementing_Client_Libraries
> It's brief, but accurate. You'll find links to the relevant pages describing
> the various protocols and formats required.
> Writing for a PIC seems like a bigger undertaking than
> Flash/Java/Objective-C, mainly because ROS does require that a node run an
> XMLRPC/HTTP server.
>  - Ken
> On Sat, Jan 9, 2010 at 7:18 PM, Ben Axelrod <ben at benaxelrod.com> wrote:
>> I am interested in this as well.  I am curious if I can make a small
>> microcontroller like a PIC with ethernet capabilities become a ROS
>> node.  This will allow much nicer interaction with low level hardware.
>> Typically, this is done by having the microcontroller talk to the
>> computer over a serial port.  And then you have a regular ROS node which
>> ferries messages between ROS and the COM port.  It would be really cool
>> to eliminate this middle man code.
>> I am new to ROS, but I am hoping that I am not too far off base here.
>> Thanks,
>> -Ben


ros-users mailing list
ros-users at lists.sourceforge.net

More information about the ros-users mailing list