I am using Ros Noetic in Ubuntu 20.02 and i am trying to move joints using rostopic to simulate a rover. I have created a simple robot with only one join and when i try to load the controller, it doesn't work. I've followed the tutorial of gazebo ros control but it doesnt work as well. My files are the following: .xacro: <?xml version="1.0" ?>

.gazebo:

<?xml version="1.0" ?>

/srob ${body_color} 0.2 0.2 true true

${body_color} 0.2 0.2 true

gazebo.launch:

controller.launch:

and controller.yaml: srob: # Publish all joint states ----------------------------------- jointstatecontroller: type: jointstatecontroller/JointStateController publish_rate: 50

# Position Controllers -------------------------------------- Revpositioncontroller: type: effort_controllers/JointPositionController joint: Rev pid: {p: 100.0, i: 0.01, d: 10.0}

The rosservice list after executing the roslaunch gazebo and controller :/controllermanager/listcontrollertypes /controllermanager/listcontrollers /controllermanager/loadcontroller /controllermanager/reloadcontrollerlibraries /controllermanager/switchcontroller /controllermanager/unloadcontroller /gazebo/applybodywrench /gazebo/applyjointeffort /gazebo/clearbodywrenches /gazebo/clearjointforces /gazebo/deletelight /gazebo/deletemodel /gazebo/getjointproperties /gazebo/getlightproperties /gazebo/getlinkproperties /gazebo/getlinkstate /gazebo/getloggers /gazebo/getmodelproperties /gazebo/getmodelstate /gazebo/getphysicsproperties /gazebo/getworldproperties /gazebo/pausephysics /gazebo/resetsimulation /gazebo/resetworld /gazebo/setjointproperties /gazebo/setlightproperties /gazebo/setlinkproperties /gazebo/setlinkstate /gazebo/setloggerlevel /gazebo/setmodelconfiguration /gazebo/setmodelstate /gazebo/setparameters /gazebo/setphysicsproperties /gazebo/spawnsdfmodel /gazebo/spawnurdfmodel /gazebo/unpausephysics /gazebogui/getloggers /gazebogui/setloggerlevel /robotstatepublisher/getloggers /robotstatepublisher/setloggerlevel /rosout/getloggers /rosout/setloggerlevel /srob/controllerspawner/getloggers /srob/controllerspawner/setloggerlevel.

As it can be seen there is srob before controller spawner but not before controllermanager. So when i try to execute the following command : rosservice call srob/controllermanager/loadcontroller "name: 'Revposition_controller'" the error message is service is not available and if i remove the srob/ the gazebo returns:

[ERROR] [1670887147.867585844]: Could not load controller 'Revpositioncontroller' because the type was not specified. Did you load the controller configuration on the parameter server (namespace: '/Revpositioncontroller')?

Thank you in advance for your help.