gazebo_ros_control plugin is waiting for model URDF in parameter [/jackal/robot_description] on the ROS param server

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I'm using ROS melodic. multimaster_fkie.

getting "gazebo_ros_control plugin is waiting for model URDF in parameter [/jackal/robot_description] on the ROS param server."

Also suggest me how can i pass this URDF in parameter on ROS param server?

-------------------------These are the logs from docker terminal------------------------

Finished loading Gazebo ROS API Plugin. waitForService: Service [/gazebo/set_physics_properties] has not been advertised, waiting... Finished loading Gazebo ROS API Plugin. waitForService: Service [/gazebo_gui/set_physics_properties] has not been advertised, waiting... waitForService: Service [/gazebo/set_physics_properties] is now available. Physics dynamic reconfigure ready. Camera Plugin: Using the 'robotNamespace' param: 'jackal/front_stereo/' Camera Plugin: Using the 'robotNamespace' param: 'jackal/front_stereo/' Camera Plugin (ns = jackal/front_stereo/) <tf_prefix_>, set to "jackal/front_stereo" Camera Plugin (ns = jackal/front_stereo/) <tf_prefix_>, set to "jackal/front_stereo" Loading gazebo_ros_control plugin Starting gazebo_ros_control plugin in namespace: jackal gazebo_ros_control plugin is waiting for model URDF in parameter [/jackal/robot_description] on the ROS param server.