This is modified version of amcl ros package. We added amcl pose updater that updates amcl_pose and the particle states when known-pose flag is detected.
cd ~/leo_ws/src
git clone https://github.com/haeyeoni/amcl_pose_updater
cd ~/leo_ws
catkin_make
Run amcl_pose_updater node
roslaunch amcl_pose_updater amcl_diff.launch
When you want to update pose with new known pose (fixed covariance)
rosservice call /pose_update new_x new_y new_theta