gazebo_extra_plugins is a ros package that can be compiled directly into the workspace to generate the required plugins.
actor.world is the world file that uses the plugin generated by itself. Note that devel/lib needs to be added to the environment variable of Gazebo before opening, otherwise it will not work properly.
Step:
roscore to run ros master.gazebo actor.world to run file.rosrun running package provides keyboard_actor_pyqt.py or keyboard_actor.py to control pedestrians. (The control methods are i->forward, j->turn left, l->turn right, the pyqt version can monitor the pressing and releasing events of the button, and the realized control is lower latency.)