Wang Han [homepage] ![Profile views](https://camo.githubusercontent.com/07ea37c0ebbad29f435525659d07a71105fcf782d9abe195b51e5e7ba63e8f65/68747470733a2f2f677076632e6172747572696f2e6465762f7768323030373230303431)
- :🌱: currently working in Huawei Singapore (Todmind Program).
- 🎓 received Ph.D. in Nanyang Technological University.
- 🔨 specialize in computer vision and robotics.
SSL_LIO: Solid-State LiDAR based LiDAR-Inertial SLAM
License: GNU General Public License v3.0
Hello @wh200720041,
Thank you for the great work.
I setup the repo on my PC (ubuntu 20.04, with noetic) and tried the ssl_slam3.launch with the standard bag file and it worked fine. When I launch the ssl_slam3_L515.launch for the live run though, I immediately get the messages "not enough correct surf points" and "not enough correct edge points" and the map spirals out. I tried with all frequencies and resolutions (for RGB and depth) and the issue is still the same.
Hoping you could assist with the same.
Hi, @wh200720041
I have test the code for a modified version of traditional spinning lidar.
The only modification is feature extraction, the moudle is implemented based on lio-sam.
After the adjustment, everything is ok ,and it seems normal with my data.
I added a distortion correction module, use the imu preintegrate predict pose. But it seems something wrong, distortion correction did not work well.
I debug the question,and find out that the imu bias is small. It is not normal.
The possible reason maybe:
Can you give me some advice?
Thanks.
hello, @wh200720041
Thanks for your great work.
I have a question about the derivation of jacobian formula in lidarOptimizationFactor.cpp
In factor LidarEdgeFactor
:
Eigen::Matrix<double, 3, 15> dp_by_so3xyz = Eigen::Matrix<double, 3, 15>::Zero();
dp_by_so3xyz.block<3, 3>(0, 0) = - Ri * Utils::skew(curr_point);
dp_by_so3xyz.block<3, 3>(0, 3) = Eigen::Matrix3d::Identity();
I'm confused about why is a Ri
here? how do you derive the formula?
Can you give me some help ?
Thanks
I tested it, it lasted for about 40ms. Dose this part really need so much time?
And does your research group accept students from CSC exchange? I want to come and study, your work really impressed me.
Hope for your reply.
Hi, @wh200720041
Thanks for your great work.
I have a question about the derivation of jacobian formula in imuOptimizationFactor.cpp.
The residual function is:
`
// residual 1 = log[delta_r' * Ri' * Rj]
// residual 2 = Ri'* (0.5 * g *dt2 + Pj - Pi -Vi * dt) - delta_p
// residual 3 = Ri'* (g * dt + Vj - Vi) - delta_v
// residual 4 = b_aj - b_ai
// residual 5 = b_gj - b_gi
`
the optimized variable is r p v ba bg
I'm confused about how do you derive the formula
`
jacobian_i.block<3, 3>(0, 0) = - Utils::Jr_so3_inv(rot_residual) * Rj.transpose() * Ri;
jacobian_i.block<3, 3>(0, 12) = - Utils::Jr_so3_inv(rot_residual) * Rj.transpose() * Ri * corrected_delta_R * dr_dbg;
`
and jacobian_j.block<3, 3>(0, 0) = Utils::Jr_so3_inv(rot_residual);
Can you give me some help?
I have a solid lidar called rslidar M1,could this code map successful on rslidar M1?
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