visual inertial calibration

I always find a way to online calibrate IMU and camera intrinsic parameters and extrinsic parameter between camera and IMU.

some good works can be saw as follow:

[1] Li M, Yu H, Zheng X, et al. High-fidelity sensor modeling and self-calibration in vision-aided inertial navigation[C]// IEEE International Conference on Robotics and Automation. IEEE, 2014:409-416.

[2] Nikolic J, Burri M, Gilitschenski I, et al. Non-Parametric Extrinsic and Intrinsic Calibration of Visual-Inertial Sensor Systems[J]. IEEE Sensors Journal, 2016, 16(13):5433-5443.

[3] Rehder J, Nikolic J, Schneider T, et al. Extending kalibr: Calibrating the extrinsics of multiple IMUs and of individual axes[C]// IEEE International Conference on Robotics and Automation. IEEE, 2016:4304-4311.

[4] Schneider T, Li M, Burri M, et al. Visual-inertial self-calibration on informative motion segments[C]// IEEE International Conference on Robotics and Automation. IEEE, 2017:6487-6494.

modern visual inertial system employ low-cost MEMS chip gyroscope and accelerometers . Due the technology use ,there can exhibit significant scale factor and misalignment. Once sensor unit undergo motion, these term cause correlated errors which quickly render a purely stochastic sensor model invalid. this lead to error in extrinsic calibration and to suboptimal performance.

so we need to calibrate the imu intrinsic parameters including scale factor , misalignment and so on.

I calibrated my oppoR11 phone by using kalibr based on[3], some procedures please see Wiki:

https://github.com/ethz-asl/kalibr/wiki

My contribute to a code whose function analogy to bagcreator, which can convert image and imu to rosbag. I had opened source it, please see :

https://github.com/QingfengLi-hit/ImageIMU_to_rosbag

some tips:

if you use kalibr to calibrate imu intrinsic ,please use similar to follow command:

kalibr_calibrate_imu_camera --bag /home/jinmuyan/dataset/kalibr/oppo/oppo.bag --cam /home/jinmuyan/dataset/kalibr/oppo/camchain.yaml --imu /home/jinmuyan/dataset/kalibr/oppo/imu_adis16448.yaml --target /home/jinmuyan/dataset/kalibr/oppo/april_6x6.yaml

My dataset come from oppoR11 can be download:

link: https://pan.baidu.com/s/1quZ48pBZb5vjT3BueMja7w password: 8syv