Hello! I recently ran the open source code of Intensity-slam whose author also proposed floam and iscloam. But when I ran the kitti 05 sequence provided by the author, I got an error reported as "[intensity_slam_isc_optimization_node -6] has died". When I used kitti_to_rosbag to convert kitti sequence for experiment, I found that this error would be reported if there was a segment of looped sequence, including the sequence 00,02, 05, 06, etc. I was wondering if you have ever run Intensity-slam or had this problem when running iscloam? I would be most appreciative if you could provide relevant suggestions and help.