<div dir="ltr"><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Jan 29, 2013 at 7:17 AM, Adolfo Rodríguez Tsouroukdissian <span dir="ltr"><<a href="mailto:adolfo.rodriguez@pal-robotics.com" target="_blank">adolfo.rodriguez@pal-robotics.com</a>></span> wrote:<br>

<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div id=":3na">Firstly I'd like to thank you all for the positive feedback the original post received. As next steps, it seems that the Willow Garage / hiDOF implementation is a good starting point, as it already allows:<br>


- Loading controllers as plugins, and serializing their execution in a single thread.<br>- Creating controllers with arbitrary hardware interfaces.<br><br>I'll be giving this a test-drive, with the immediate steps being to:<br>


- Write an Orocos 2.6 based component that leverages the controller_manager library.<br>- Trigger each controller with a dedicated, configurable timer event to allow each controller to have its own update rate. This timer event should be compatible with deployment in hard-realtime and simulated clock contexts.<br>

</div></blockquote></div><br>Adolpho,</div><div class="gmail_extra"><br></div><div class="gmail_extra">If you're interested in help with integrating ros_control with orocos, I'd be happy to contribute, as I was already planning on trying something similar in a few weeks from now.<br>

</div><div class="gmail_extra"><br></div><div class="gmail_extra"><div class="gmail_extra">With respect to hard realtime (xenomai) and ROS sim time, I wrote a simple tool as part of my own architecture about a year ago [1]. It's made to just query the time, but I think something similar could be done to switch between timers.</div>

</div><div class="gmail_extra"><br></div><div class="gmail_extra" style>[1] <a href="https://github.com/jhu-lcsr/lcsr_ros_orocos_tools/blob/master/rtt_ros_tools/include/rtt_ros_tools/time.h#L36">https://github.com/jhu-lcsr/lcsr_ros_orocos_tools/blob/master/rtt_ros_tools/include/rtt_ros_tools/time.h#L36</a><br>

</div><div class="gmail_extra"><br></div><div class="gmail_extra"><div class="gmail_extra">Also, thanks for starting this conversation!</div><div class="gmail_extra"><br></div></div><div class="gmail_extra" style>-jon</div>

<div class="gmail_extra"><div><br></div><div style>ps - I also ported the old PR2 JointSplineTrajectoryController into an orocos environment last year [2], and it'd be interesting to compare ports!</div><div class="gmail_extra">

<br></div><div class="gmail_extra">[2] <a href="https://github.com/jhu-lcsr/controllerman/blob/master/controllerman_controllers/src/trajectory_dispatcher.cpp">https://github.com/jhu-lcsr/controllerman/blob/master/controllerman_controllers/src/trajectory_dispatcher.cpp</a></div>

<div><br></div>-- <br><div style="font-family:arial,sans-serif;font-size:13px"><span style="background-color:rgb(255,255,255)">Jonathan Bohren</span></div><div style="font-family:arial,sans-serif;font-size:13px"><span style="background-color:rgb(255,255,255)">PhD Student</span></div>

<div style="font-family:arial,sans-serif;font-size:13px"><span style="background-color:rgb(255,255,255)">Dynamical Systems and Control Laboratory</span></div><div style="font-family:arial,sans-serif;font-size:13px"><span style="background-color:rgb(255,255,255)">Laboratory for Computational Sensing and Robotics</span></div>

<div style="font-family:arial,sans-serif;font-size:13px"><span style="background-color:rgb(255,255,255)">The Johns Hopkins University</span></div><div style="font-family:arial,sans-serif;font-size:13px"><span style="background-color:rgb(255,255,255)"><br>

</span></div><div style="font-family:arial,sans-serif;font-size:13px"><font style="background-color:rgb(255,255,255)" color="#000000">(707) 520-4736</font></div><div style="font-family:arial,sans-serif;font-size:13px"><font style="background-color:rgb(255,255,255)" color="#000000"><a href="mailto:jbo@jhu.edu" target="_blank">jbo@jhu.edu</a></font></div>


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