That error is due to a lack of the PLUGINLIB_DECLARE_CLASS macro.  See
http://www.ros.org/wiki/pluginlib/Troubleshooting

Tully

On Tue, Aug 3, 2010 at 11:59 AM, Stuart Glaser <sglaser@willowgarage.com>wrote:

> Hi Koen,
>
> This error:
>
> Cannot load library: No manifest in
>
> /home/kbuys/ros/private-kul-ros-pkg/ros_controller_tutorials/my_controller_pkg/lib/libmy_controller_lib.so:
> MyControllerPlugin"
>
> indicates that the library was built incorrectly.  Pluginlib searches
> the library for a particular symbol in order to find the plugins, and
> this error explains that it couldn't find the symbol.  Run the
> following to see what plugins the library contains:
>
> nm lib/libmy_controller_lib.so  | grep pocoBuildManifest
>
> Is your plugin listed?
>
> -Stu
>
> On Tue, Aug 3, 2010 at 11:02 AM, koen buys <koen.buys@mech.kuleuven.be>
> wrote:
> > $ cat controller_plugins.xml
> > <library path="lib/libmy_controller_lib">
> >  <class name="MyControllerPlugin"
> >         type="my_controller_ns::MyControllerClass"
> >         base_class_type="pr2_controller_interface::Controller" />
> > </library>
> >
> >
> > On 3 August 2010 18:44, Rob Wheeler <wheeler@willowgarage.com> wrote:
> >> What does your controller_plugins.xml file look like?
> >>
> >> -R
> >>
> >> On Tue, Aug 3, 2010 at 7:23 AM, koen buys <koen.buys@mech.kuleuven.be>
> >> wrote:
> >>>
> >>> Hi all,
> >>>
> >>> I'm trying to run the following tutorial:
> >>>
> >>>
> http://www.ros.org/wiki/pr2_mechanism/Tutorials/Running%20a%20realtime%20joint%20controller
> >>> Rxconsole is giving me the following error:
> >>>
> >>> "Could not load class MyControllerPlugin: Failed to load library
> >>>
> >>>
> /home/kbuys/ros/private-kul-ros-pkg/ros_controller_tutorials/my_controller_pkg/lib/libmy_controller_lib.so.
> >>> Make sure that you are calling the PLUGINLIB_REGISTER_CLASS macro in
> >>> the library code, and that names are consistent between this macro and
> >>> your XML. Error string: Cannot load library: No manifest in
> >>>
> >>>
> /home/kbuys/ros/private-kul-ros-pkg/ros_controller_tutorials/my_controller_pkg/lib/libmy_controller_lib.so:
> >>> MyControllerPlugin"
> >>>
> >>> Together with the following error after:
> >>>
> >>> "Could not load controller 'my_controller_name' because controller
> >>> type 'MyControllerPlugin' does not exist"
> >>>
> >>> We couldn't find the cause of it. When I did a :
> >>>
> >>> $ rosrun pr2_controller_manager pr2_controller_manager list-types
> >>> CartesianTrajectoryController
> >>> ContactObserverPlugin
> >>> JTTeleopController
> >>> JointGravityController
> >>> JointPendulumController
> >>> MyControllerPlugin
> >>> SlipGripControllerPlugin
> >>> SrhFakeJointCalibrationController
> >>> StanfordWBCPump
> >>> VelController
> >>> ethercat_trigger_controllers/MultiTriggerController
> >>> ethercat_trigger_controllers/ProjectorController
> >>> ethercat_trigger_controllers/TriggerController
> >>> ft_eval/PoseForceController
> >>> ft_eval/TwistForceController
> >>> joint_qualification_controllers/CheckoutController
> >>> joint_qualification_controllers/CounterbalanceTestController
> >>> joint_qualification_controllers/HeadPositionController
> >>> joint_qualification_controllers/HysteresisController
> >>> joint_qualification_controllers/JointLimitCalibrationController
> >>> joint_qualification_controllers/MotorJointCalibrationController
> >>> joint_qualification_controllers/WristDifferenceController
> >>> pr2_calibration_controllers/CasterCalibrationController
> >>> pr2_calibration_controllers/GripperCalibrationController
> >>> pr2_calibration_controllers/JointCalibrationController
> >>> pr2_calibration_controllers/WristCalibrationController
> >>> pr2_controller_manager/TestController
> >>> pr2_mechanism_controllers/CasterController
> >>> pr2_mechanism_controllers/CasterControllerNode
> >>> pr2_mechanism_controllers/LaserScannerTrajController
> >>> pr2_mechanism_controllers/Pr2BaseController
> >>> pr2_mechanism_controllers/Pr2BaseController2
> >>> pr2_mechanism_controllers/Pr2GripperController
> >>> pr2_mechanism_controllers/Pr2Odometry
> >>> robot_mechanism_controllers/CartesianPoseController
> >>> robot_mechanism_controllers/CartesianTwistController
> >>> robot_mechanism_controllers/CartesianWrenchController
> >>> robot_mechanism_controllers/JointEffortController
> >>> robot_mechanism_controllers/JointPositionController
> >>> robot_mechanism_controllers/JointSplineTrajectoryController
> >>> robot_mechanism_controllers/JointTrajectoryActionController
> >>> robot_mechanism_controllers/JointVelocityController
> >>> rttuning_controllers/JointTuningController
> >>> teleop_controllers/JinvTeleopController7
> >>> tff_controller/TFFController
> >>> tirt/TirtController
> >>>
> >>> It shows up. However now:
> >>>
> >>> $ rosrun pr2_controller_manager pr2_controller_manager load
> >>> MyControllerPlugin
> >>> Error when loading MyControllerPlugin
> >>>
> >>> This is my manifest:
> >>>
> >>> <package>
> >>>  <description brief="my_controller_pkg">
> >>>
> >>>     my_controller_pkg
> >>>
> >>>  </description>
> >>>  <author>Koen</author>
> >>>  <license>BSD</license>
> >>>  <review status="unreviewed" notes=""/>
> >>>  <url>http://ros.org/wiki/my_controller_pkg</url>
> >>>  <depend package="pr2_controller_interface"/>
> >>>  <depend package="pr2_mechanism_model"/>
> >>>  <depend package="pluginlib"/>
> >>>  <export>
> >>>    <pr2_controller_interface plugin="${prefix}/controller_plugins.xml"
> />
> >>>  </export>
> >>> </package>
> >>>
> >>> This is my CMakeLists:
> >>>
> >>> cmake_minimum_required(VERSION 2.4.6)
> >>> include($ENV{ROS_ROOT}/core/rosbuild/rosbuild.cmake)
> >>>
> >>> # Set the build type.  Options are:
> >>> #  Coverage       : w/ debug symbols, w/o optimization, w/
> code-coverage
> >>> #  Debug          : w/ debug symbols, w/o optimization
> >>> #  Release        : w/o debug symbols, w/ optimization
> >>> #  RelWithDebInfo : w/ debug symbols, w/ optimization
> >>> #  MinSizeRel     : w/o debug symbols, w/ optimization, stripped
> binaries
> >>> #set(ROS_BUILD_TYPE RelWithDebInfo)
> >>>
> >>> rosbuild_init()
> >>>
> >>> #set the default path for built executables to the "bin" directory
> >>> set(EXECUTABLE_OUTPUT_PATH ${PROJECT_SOURCE_DIR}/bin)
> >>> #set the default path for built libraries to the "lib" directory
> >>> set(LIBRARY_OUTPUT_PATH ${PROJECT_SOURCE_DIR}/lib)
> >>>
> >>> #uncomment if you have defined messages
> >>> #rosbuild_genmsg()
> >>> #uncomment if you have defined services
> >>> #rosbuild_gensrv()
> >>>
> >>> #common commands for building c++ executables and libraries
> >>> #rosbuild_add_library(${PROJECT_NAME} src/example.cpp)
> >>> #target_link_libraries(${PROJECT_NAME} another_library)
> >>> #rosbuild_add_boost_directories()
> >>> #rosbuild_link_boost(${PROJECT_NAME} thread)
> >>> #rosbuild_add_executable(example examples/example.cpp)
> >>> #target_link_libraries(example ${PROJECT_NAME})
> >>> rosbuild_add_library(my_controller_lib src/my_controller_file.cpp)
> >>>
> >>> And this is the content of my source file:
> >>>
> >>> #include "my_controller_pkg/my_controller_file.h"
> >>> #include <pluginlib/class_list_macros.h>
> >>>
> >>> using namespace my_controller_ns;
> >>>
> >>> /// Register controller to pluginlib
> >>> PLUGINLIB_REGISTER_CLASS(MyControllerPlugin,
> >>>                         my_controller_ns::MyControllerClass,
> >>>                         pr2_controller_interface::Controller)
> >>>
> >>> /// Controller initialization in non-realtime
> >>> bool MyControllerClass::init(pr2_mechanism_model::RobotState *robot,
> >>>                            ros::NodeHandle &n)
> >>> {
> >>>  std::string joint_name;
> >>>  if (!n.getParam("joint_name", joint_name))
> >>>  {
> >>>    ROS_ERROR("No joint given in namespace: '%s')",
> >>>              n.getNamespace().c_str());
> >>>    return false;
> >>>  }
> >>>
> >>>  joint_state_ = robot->getJointState(joint_name);
> >>>  if (!joint_state_)
> >>>  {
> >>>    ROS_ERROR("MyController could not find joint named '%s'",
> >>>              joint_name.c_str());
> >>>    return false;
> >>>  }
> >>>  return true;
> >>> }
> >>>
> >>>
> >>> /// Controller startup in realtime
> >>> void MyControllerClass::starting()
> >>> {
> >>>  init_pos_ = joint_state_->position_;
> >>> }
> >>>
> >>>
> >>> /// Controller update loop in realtime
> >>> void MyControllerClass::update()
> >>> {
> >>>  double desired_pos = init_pos_ + 0.5 * sin(ros::Time::now().toSec());
> >>>  double current_pos = joint_state_->position_;
> >>>  joint_state_->commanded_effort_ = -10 * (current_pos - desired_pos);
> >>> }
> >>>
> >>>
> >>> /// Controller stopping in realtime
> >>> void MyControllerClass::stopping()
> >>> {}
> >>> _______________________________________________
> >>> ros-users mailing list
> >>> ros-users@code.ros.org
> >>> https://code.ros.org/mailman/listinfo/ros-users
> >>
> >>
> > _______________________________________________
> > ros-users mailing list
> > ros-users@code.ros.org
> > https://code.ros.org/mailman/listinfo/ros-users
> >
>
>
>
> --
> Stuart Glaser
> sglaser -at- willowgarage -dot- com
> www.willowgarage.com
> _______________________________________________
> ros-users mailing list
> ros-users@code.ros.org
> https://code.ros.org/mailman/listinfo/ros-users
>



-- 
Tully Foote
Systems Engineer
Willow Garage, Inc.
tfoote@willowgarage.com
(650) 475-2827