Hello RIcardo,
I did what you suggested me. Actually, using echo the cmd_vel command are coerent with the letters typed. So the problem is on the URDF code. At moment, I am still looking for the issue. I think the problem could be in the differential drive pluigin or more probably in the controller…I added <command_topic>cmd_vel_</command_topic> the missed in the lesson…but nothing of different.
<!-- wheels -->
<left_joint>chassis_left_wheel_joint</left_joint>
<right_joint>chassis_right_wheel_joint</right_joint>
<!-- kinematics -->
<wheel_separation>1.0912</wheel_separation>
<wheel_diameter>0.206</wheel_diameter>
<!-- limits -->
<max_wheel_torque>20.0</max_wheel_torque>
<max_wheel_acceleration>2.0</max_wheel_acceleration>
<command_topic>cmd_vel</command_topic>
<remapping>/cmd_vel:=amrj16/cmd_vel</remapping>
<!-- output -->
<publish_odom>true</publish_odom>
<publish_odom_tf>true</publish_odom_tf>
<publish_wheel_tf>false</publish_wheel_tf>
<odometry_topic>odom</odometry_topic>
<odometry_frame>odom</odometry_frame>
<robot_base_frame>base_link</robot_base_frame>
</plugin>
thanks for any suggestions
Salvatore