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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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"EstimateGyroBias",why ignore extrinsic parameters beween IMU and Lidar? #76

Open ZzJiachenchen opened 3 years ago

ZzJiachenchen commented 3 years ago

why in function "EstimateGyroBias", when estimating gyro bias of IMU, there can ignore the extrinsic parameters beween IMU and Lidar?

 Eigen::Quaterniond q_ij(laser_trans_i.second.transform.rot.conjugate() * laser_trans_j.second.transform.rot);

tmp_A = laser_trans_j.second.pre_integration->jacobian_.template block<3, 3>(O_R, O_BG);
 /// Jacobian of dr12_bg

tmp_b = 2 * (laser_trans_j.second.pre_integration->delta_q_.conjugate() * q_ij).vec();
 /// 2*vec(IMU_ij^T * q_ij)

Why tmp_b is not :

2*vec(IMU_ij^T *(rbl* q_ij* rlb))

Thanks a lot!