how to get the initial pose of robot in explore_lite

edit

Hi, I am a beginner that doing the multiple robot exploration projects, the algorithm in my mind is to reflect the initial poses of several robots, but if I created my own outside node and directly use subscriber to subscribe the geometry_msgs::PoseWithCovarianceStamped::ConstPtr& msg, and try to use ROS_INFO to show it, it's not work. I was tested my own node source code worked well, so it is not the form problem. Thanks for all solvers By the way, the robot type is turtlebot3