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hyye / lio-mapping

Implementation of Tightly Coupled 3D Lidar Inertial Odometry and Mapping (LIO-mapping)
https://sites.google.com/view/lio-mapping
GNU General Public License v3.0
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imu excitation is not enouth #17

Closed pxc2017 closed 4 years ago

pxc2017 commented 4 years ago

Hello，hyye.First,thanks for your open work,that is so amazing.im green in SLAM. I just confused about why “imu excitation is not enouth”appeared while using my own dataset,and about one minute later,with the imu initialized successfully,the map occurred but the datas in that one minute has lost.Is frequency of the imu not high enough?I used the MTi Xsens 100Hz,RS-16 10Hz BTW,should it be "enough",i also saw "enouth"in the source code. thank you very much!

hyye commented 4 years ago

It's a typo in the code. The excitation is not enough means that the current motion is not enough for IMU to be initialized, like constant velocity, no rotation. This behavior ensures the system has a good initial value for further optimization.

BTW, if you use Xsens, it might be better to set your IMU with a higher frequency.

pxc2017 commented 4 years ago

really appreciate for your answer,i will make a try.

llu0120 commented 4 years ago

Hi, I also confront this problem, that my IMU frequency is 50 Hz, will this lead the not initialized IMU?

hyye commented 4 years ago

@llu0120, see more discussions in https://github.com/hyye/lio-mapping/issues/22.