为什么使用esekfom::esekf时不用模板？我看FAST_LIO2里是esekfom::esekf<state_ikfom, 12, input_ikfom>，不用模板会有问题吗？

The simplified code does achieve slightly worse results than the source code.
However, there is an obvious bug in the map saving step. Just save pcl_wait_save directly, no need to read the point cloud in the folder and then merging.

Hello Sir, Thank your FAST-LIO paper.
I found that the FAST-LIO paper that you provide is Chinese version only.
Could I get a Engilsh version of FAST-LIO paper?
Thank you

any plans to optimise the CPU usage ?

王博您好，感谢您开源的S-FAST-LIO。
在按照readme中的安装方法安装Sophus时遇到了问题，git checkout a621ff后，编译失败，报错是存在一个非法左值赋值。用最新分支main-1.x的最新commit编译后，Sophus安装成功。但是在编译S-FAST-LIO时发现引用头文件时名称不一致（估计是Sophus不一致导致的）导致报错。看报错都是代码里使用Sophus::SO3时与我安装的Sophus版本不一致。
我想知道您的源代码具体用的是Sophus哪个分支的哪个commit编译的，期待您的回复

您好，請問您的F_X中是不是缺少了EXP(-w^ *t )。

和FAST_LIO对比，这个变量没什么变化，为什么size是0

把最后的保存地图阶段去掉这个变量，改为

    if (pcd_save_en)
    {

如果建图时间短，可以建图，如果时间长了仍然不能正常保存，合并pcd失败了吗？

(slam_env) root@P3551-KUANZHANG:~/catkin_ws# source /catkin_ws/devel/setup.bash
(slam_env) root@P3551-KUANZHANG:/catkin_ws# roslaunch sfast_lio mapping_avia.launch
... logging to /root/.ros/log/88aab05c-5da9-11ee-a076-00155d1f1638/roslaunch-P3551-KUANZHANG-24868.log
Checking log directory for disk usage. This may take a while.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://P3551-KUANZHANG:46727/

SUMMARY

PARAMETERS

• /common/imu_topic: /livox/imu
• /common/lid_topic: /livox/lidar
• /common/time_offset_lidar_to_imu: 0.0
• /common/time_sync_en: False
• /cube_side_length: 1000.0
• /feature_extract_enable: False
• /filter_size_map: 0.5
• /filter_size_surf: 0.5
• /mapping/acc_cov: 0.1
• /mapping/b_acc_cov: 0.0001
• /mapping/b_gyr_cov: 0.0001
• /mapping/det_range: 450.0
• /mapping/extrinsic_R: [1, 0, 0, 0, 1, 0...
• /mapping/extrinsic_T: [0.04165, 0.02326...
• /mapping/extrinsic_est_en: False
• /mapping/fov_degree: 90
• /mapping/gyr_cov: 0.1
• /max_iteration: 3
• /pcd_save/interval: 100
• /pcd_save/pcd_save_en: False
• /point_filter_num: 2
• /preprocess/blind: 4
• /preprocess/lidar_type: 1
• /preprocess/scan_line: 6
• /publish/dense_publish_en: True
• /publish/path_en: True
• /publish/scan_bodyframe_pub_en: False
• /publish/scan_publish_en: True
• /rosdistro: noetic
• /rosversion: 1.16.0

NODES
/
laserMapping (sfast_lio/fastlio_mapping)
rviz (rviz/rviz)

ROS_MASTER_URI=http://localhost:11311

ERROR: cannot launch node of type [sfast_lio/fastlio_mapping]: Cannot locate node of type [fastlio_mapping] in package [sfast_lio]. Make sure file exists in package path and permission is set to executable (chmod +x)
process[rviz-2]: started with pid [24893]
qt.qpa.xcb: could not connect to display 127.0.0.1:0
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.

[rviz-2] process has died [pid 24893, exit code -6, cmd nice /opt/ros/noetic/lib/rviz/rviz -d /root/catkin_ws/src/S-FAST_LIO/rviz_cfg/loam_livox.rviz __name:=rviz __log:=/root/.ros/log/88aab05c-5da9-11ee-a076-00155d1f1638/rviz-2.log].
log file: /root/.ros/log/88aab05c-5da9-11ee-a076-00155d1f1638/rviz-2*.log
all processes on machine have died, roslaunch will exit
shutting down processing monitor...
... shutting down processing monitor complete
done

@zlwang7
Thank you for sharing an awesome project!

By the way, I read your personal blog, but I can't access the text description in PDF.
Can you give me a link to access it from abroad?

If you could share a link to it on google drive or Onedrive, I would be very grateful.

Thanks,

Hello,
I read your blog post about FAST-LIO and I have some questions about formula (28)
$Exp(E)Exp(A(E)^T\Delta E) = d^{-1}\cdot a \cdot Exp(b)Exp(A(b)^T\Delta b)\cdot Exp(c)$

From, $Exp(E) = d^{-1}\cdot a \cdot Exp(b) \cdot Exp(c) $
We can write $Exp(E) \cdot Exp^{-1}(c) = d^{-1} \cdot a \cdot Exp(b)$

Therefore, $Exp(E)Exp(A(E)^T\Delta E) = Exp(E) \cdot Exp^{-1}(c)Exp(A(b)^T\Delta b)\cdot Exp(c)$
$\therefore Exp(A(E)^T\Delta E) = Exp^{-1}(c)Exp(A(b)^T\Delta b)\cdot Exp(c)$

But in you blog post, It is written $Exp(A(E)^T\Delta E) = Exp(-c)Exp(A(b)^T\Delta b)\cdot Exp(c)$
Is it possible to use $Exp^{-1}(c)$ as a $Exp(-c)$ ?