ArduCopter simulator failed to load plugins Tutorial

I have already setup SITL in this tutorial: --> click me <–

I am following this simulation ArduCopter Tutorial: --> click me <–

In the Section of: “Start the Simulator”, after running this commands

cd ~/gazebo
gazebo --verbose worlds/

When Gazebo Terminal loads, output a lot of ‘Failed to load plugin

Like for example:

 [Err] [Plugin.hh:180] Failed to load plugin cannot open shared object file: No such file or directory

Why the plugins aren’t loading correctly? How can I solve this?

Because the lib is installed by command “sudo make install”, so the .so file access permission is denied when we try to start the simulation by “gazebo --verbose worlds/”.
Try this, good luck!
sudo gazebo --verbose worlds/