<p>Hai-<br>
     We need to put something in the tutorials about this, because I think this confused a lot of people in the workshop. The controllers are loaded by the pr2_controller_manager, which is part of the realtime loop node. This system uses pluginlib to load the controllers. Pluginlib searches for controllers using the ROS_PACKAGE_PATH from the process that started it.<br>

      First of all, make sure you have properly built the controllers. Make sure the controllers package is in your environment. Check for the controller plugin using rospack.<br>
      If the controller plugin is properly set up, you'll need to launch the robot using the correct environment. You can either use "sudo robot start -e", or run "roslaunch /etc/ros/robot.launch". This will launch the robot with the controller manager pointed at the right place.</p>

<p>Kevin</p>
<p><blockquote type="cite">On Jun 22, 2010 9:01 PM, "Hai Nguyen" <<a href="mailto:haidai@gmail.com">haidai@gmail.com</a>> wrote:<br><br>Hi,<br>
<br>
I'm trying to get the JTTelopController running on our robot.  At<br>
first, I checked out the version tagged for cturtle but the<br>
telop_controllers package had a ROS_BUILD_BLACKLIST in it so I moved<br>
on to 'latest' (r39163).  From latest I found the launch files<br>
formerly in cartesian_controller_tutorial in telop_microscribe,<br>
launched c_jt.launch (a file that we were using during the workshop),<br>
but then I received errors about something failing to load the<br>
controllers (see below).  Have you seen these errors before and<br>
possibly know how to fix them?<br>
<br>
Errors from roslaunch:<br>
[ERROR] 1277263944.599523: Failed to load l_cart<br>
[ERROR] 1277263945.605297: Failed to load r_cart<br>
<br>
Errors from rosout:<br>
Node: /realtime_loop<br>
Could not load controller 'l_cart' because controller type<br>
'JTTeleopController' does not exist<br>
<br>
Node: /realtime_loop<br>
Could not load class JTTeleopController: According to the loaded<br>
plugin descriptions the class JTTeleopController with base class type<br>
pr2_controller_interface::Controller does not exist. Declared types<br>
are  CasterCalibrationController CheckoutController<br>
CounterbalanceTestController GripperCalibrationController<br>
HeadPositionController HysteresisController JointCalibrationController<br>
JointLimitCalibrationController MotorJointCalibrationController<br>
TFFController TestController WristCalibrationController<br>
WristDifferenceController<br>
ethercat_trigger_controllers/MultiTriggerController<br>
ethercat_trigger_controllers/ProjectorController<br>
ethercat_trigger_controllers/TriggerController<br>
pr2_mechanism_controllers/CasterController<br>
pr2_mechanism_controllers/CasterControllerNode<br>
pr2_mechanism_controllers/LaserScannerTrajController<br>
pr2_mechanism_controllers/Pr2BaseController<br>
pr2_mechanism_controllers/Pr2BaseController2<br>
pr2_mechanism_controllers/Pr2GripperController<br>
pr2_mechanism_controllers/Pr2Odometry<br>
robot_mechanism_controllers/CartesianPoseController<br>
robot_mechanism_controllers/CartesianTwistController<br>
robot_mechanism_controllers/CartesianWrenchController<br>
robot_mechanism_controllers/JointEffortController<br>
robot_mechanism_controllers/JointPositionController<br>
robot_mechanism_controllers/JointSplineTrajectoryController<br>
robot_mechanism_controllers/JointTrajectoryActionController<br>
robot_mechanism_controllers/JointVelocityController<br>
<p><font color="#500050"><br><br>On Wed, Jun 2, 2010 at 8:04 PM, Stuart Glaser <<a href="mailto:sglaser@willowgarage.com">sglaser@willowgarage.com</a>> wrote:<br>> Hi all,<br>><br>> I'm ...</font></p><font color="#888888">--<br>

Hai Nguyen<br>
CS, Robotics<br>
</font><p><font color="#500050">_______________________________________________<br>ros-users mailing list<br><a href="mailto:ros-users@code.ros.org">ros-users@code.ros.org</a><br>https:...</font></p></blockquote></p>