ERROR] [rightWheel_effort_controller.

[DavidHan008]

ERROR] [1521098708.769688247, 0.249000000]: Exception thrown while initializing controller rightWheel_effort_controller.
Could not find resource 'right_wheel_hinge' in 'hardware_interface::EffortJointInterface'.
[ERROR] [1521098708.769856563, 0.249000000]: Initializing controller 'rightWheel_effort_controller' failed

[prath1996]

First, you have to install ros-control packages for your ros-version.
For melodic:

sudo apt-get install ros-melodic-ros-control ros-melodic-ros-controllers

Then you need to make a change in ~/catkin_ws/src/mybot_description/urdf/macros.xacro
Add hardware inside joint inside transmission tag.

<transmission name="${lr}_trans">
        <type>transmission_interface/SimpleTransmission</type>
        <joint name="${lr}_wheel_hinge">
          
           <hardwareInterface>EffortJointInterface</hardwareInterface>

        </joint>
        <actuator name="${lr}Motor">
          <hardwareInterface>EffortJointInterface</hardwareInterface>
          <mechanicalReduction>10</mechanicalReduction>
        </actuator>
      </transmission> 

You need the hardware inside your actuator as well as your joint.

[subodh-malgonde]

Works like a charm! I was stuck on this for 2 days. Had no idea how and where to fix this.

@prath1996 If I may ask, how did you figure out this solution?

[prath1996]

The reference for the above can be found on: http://wiki.ros.org/urdf/XML/Transmission
It also states that the correct place to add the <hardware interface> tag is inside the <joint> tag.
Only in versions prior to indigo, the <hardware interface> tag has to be inside <actuator> tag.
You can have a look at: ros-controls/ros_control#164

[wolfv]

How about opening a PR?