Problem occurs when use joystick and yocs_velocity_smoother to let the velocity to be more smoother [closed]

edit

Hello everyone, When I try to choose turtlesim , joystick , nodelet and add yocs_velocity_smoother to test if the velocity will become more smoother, some strange things happen. When I send a velocity to the turtle, the turtle has a very low velocity and if I stop sending the velocity , the turtle will keep the velocity. Only if I press the button which is for deadman, the velocity will start to be lower and turn to zero finally. I wonder I'm not using launch rightly. Here I put some codes in my .launch document.

===================================================================================================

<include file="$(find sensor_learning)/launch/includes/velocity_smoother.launch.xml"/>

<node pkg="nodelet" type="nodelet" name="nodelet_manager" args="manager"/> <node pkg="nodelet" type="nodelet" name="velocity_smoother" args="load yocs_velocity_smoother/VelocitySmootherNodelet nodelet_manager" output="screen">

<rosparam file = "$(find yocs_velocity_smoother)/param/standalone.yaml" command = "load"  />
<remap from = "velocity_smoother/raw_cmd_vel" to= "/turtle1/cmd_vel"/>
<!-- Input velocity-->
<remap from = "velocity_smoother/robot_cmd_vel" to="/turtle1/cmd_vel/out_put"/>
<!-- Feedback velocity -->
<remap from = "velocity_smoother/smooth_cmd_vel" to="/turtle1/cmd_vel"/>
<!-- Output velocity -->

</node>