STRANGE ERROR! Unable to move Revolute Joints in Gazebo

edit

I'm running : 1. ROS Indigo 2. Ubuntu 14.04 Trusty

I'm simulating a 6DOF robotic arm using ros_control and using gazebo_ros_control plugins. I'm using Joint Position Controllers.

I have set up the .yaml file containing the type of controllers. I have also added all the transmission and gazebo_ros_control tags in my URDF file.

Everything launches without any error. When I try to publish messages on

/nymble_arm/joint2_position_controller/command std_msgs/Float64 1.0

This is my rostopic list.

/clock
/gazebo/link_states
/gazebo/model_states
/gazebo/parameter_descriptions
/gazebo/parameter_updates
/gazebo/set_link_state
/gazebo/set_model_state
/nymble_arm/joint1_position_controller/command
/nymble_arm/joint2_position_controller/command
/nymble_arm/joint3_position_controller/command
/nymble_arm/joint4_position_controller/command
/nymble_arm/joint5_position_controller/command
/nymble_arm/joint6_position_controller/command
/nymble_arm/joint_states
/rosout
/rosout_agg
/tf
/tf_static

I'm unable to move the revolute joints. Interestingly I have two continuous joints among my 6DOF which move.

When I publish a message on revolute joints nothing happens.

rohin@dreamworks:~$ rostopic pub /nymble_arm/joint2_position_controller/command std_msgs/Float64 1.0
publishing and latching message. Press ctrl-C to terminate

Also these movements are abrupt and not in a smooth manner. Whereas I've tried tutorials where the arm follows a smoother motion using Joint Position Controllers.

How should I get my revolute joints to move? Please help!

edit