using direct linear method to calibrate the odometry estimation, by sloving A^T *A x = A^T *b with Cholesky decompose
usage step: 1.mkdir odom_ws cd ./odom_ws
2.mkdir src mv <calib_odom>(the file path of the "calib_odom") ./
cd ..
3.catkin_init_workspace
4.source ./devel/setup.bash
5.catkin_make
6.goto the launch path and execute roslaunch calib_odom odomCalib.launch
7.then uncompress the bag file
8.rosrun rviz rivz set the fix_frame as odom and add three tpic:odom_path_pub,calib_path_pub,scan_path_pub,and change the color whatever you like
9.goto the odom_ws/bag,uncompress the bag file and execute: rosbag play --clock odom.bag
10.and you will see two trajectory(one from odometry,one from scan)
11.after the bag go to the end you can open a terminal and public an topic:rostopic pub /calib_flag std_msgs/Empty "{}"
the calibrated trajectory will gained as well the calibration matrix