How can I visualise the ultrasonic sensor in Gazebo?

I want to add a gazebo plugin which is called 'sonar'. Here is my code that I took from the source:0.25 0 0 0 0 0true551.0-0.250.2551-0.250.250.010.750.010.005true5/genius/sonarultrasonic0.5ultrasound I have added visualize to be true but in a gazebo simulation I can't see the cone shaped array from the sonar. What am i doing wrong here? Btw, I have added links and joints in my main xacro file, so the fault isn't there.