i just use the kalibr to caliibrate the imu and camera.
my imu is the ttl-485 wit HWT905-485,just one request and one answer.
first i just record a rosbag by subing the /imu and /usb_image_rect_raw.and one is 150hz another is 4hz.
second i can calibrate.
i think my rosbag time has no problem.but it show me that "The time sequence must be nondecreasing".I have no idea.
how can i check it?
while i run
rosrun kalibr kalibr_calibrate_imu_camera --target /home/april_s.yaml --cam ./result/camera_calibration-camchain.yaml --imu ./result/imu.yaml --bag ./bag/camera_imu_calibration.bag --bag-from-to 5 130
in shell the error will show
Initializing a pose spline with 14936 knots (100.000000 knots per second over 149.355158 seconds)
Traceback (most recent call last):
File "/home/kalibr_workspace/src/kalibr/aslam_offline_calibration/kalibr/python/kalibr_calibrate_imu_camera", line 247, in <module>
main()
File "/home/kalibr_workspace/src/kalibr/aslam_offline_calibration/kalibr/python/kalibr_calibrate_imu_camera", line 200, in main
verbose = parsed.verbose)
File "/home/kalibr_workspace/src/kalibr/aslam_offline_calibration/kalibr/python/kalibr_imu_camera_calibration/IccCalibrator.py", line 105, in buildProblem
cam.findTimeshiftCameraImuPrior(self.ImuList[0], verbose)
File "/home/kalibr_workspace/src/kalibr/aslam_offline_calibration/kalibr/python/kalibr_imu_camera_calibration/IccSensors.py", line 221, in findTimeshiftCameraImuPrior
poseSpline = self.initPoseSplineFromCamera( timeOffsetPadding=0.0 )
File "/home/kalibr_workspace/src/kalibr/aslam_offline_calibration/kalibr/python/kalibr_imu_camera_calibration/IccSensors.py", line 315, in initPoseSplineFromCamera
pose.initPoseSplineSparse(times, curve, knots, 1e-4)
RuntimeError: [Exception] /home/kalibr_workspace/src/kalibr/aslam_nonparametric_estimation/bsplines/src/BSpline.cpp:975: initSplineSparse() assert(times[i-1] <= times[i]) failed [1.68404e+09 <= 1.68404e+09]: The time sequence must be nondecreasing. time 5 was not greater than or equal to time 4
so i guess the problem is the time between the imu and camera. i check the rosbag info
path: ./bag/camera_imu_calibration.bag
version: 2.0
duration: 2:42s (162s)
start: May 14 2023 14:51:41.29 (1684043501.29)
end: May 14 2023 14:54:24.06 (1684043664.06)
size: 518.5 MB
messages: 14378
compression: none [585/585 chunks]
types: sensor_msgs/Image [060021388200f6f0f447d0fcd9c64743]
sensor_msgs/Imu [6a62c6daae103f4ff57a132d6f95cec2]
topics: /imu 13794 msgs : sensor_msgs/Imu
/usb_image_rect_raw 584 msgs : sensor_msgs/Image
---
and i check the /imu info by using ros_readbagfile this the part of the info
# timestamp (sec): 1684043501.291285276
# timestamp (sec): 1684043501.303655624
# timestamp (sec): 1684043501.310484409
# timestamp (sec): 1684043501.323313475
# timestamp (sec): 1684043501.334561825
# timestamp (sec): 1684043501.346612692
# timestamp (sec): 1684043501.358899117
# timestamp (sec): 1684043501.370918989
# timestamp (sec): 1684043501.382922411
# timestamp (sec): 1684043501.396509409
# timestamp (sec): 1684043501.408326149
# timestamp (sec): 1684043501.420297861
# timestamp (sec): 1684043501.427345276
# timestamp (sec): 1684043501.439752579
# timestamp (sec): 1684043501.451758862
and i check the camera rostopic by using ros_readbagfile this is a part of the info
# timestamp (sec): 1684043501.335471392
# timestamp (sec): 1684043501.610888243
# timestamp (sec): 1684043501.895060062
# timestamp (sec): 1684043502.170825481
# timestamp (sec): 1684043502.454141140
# timestamp (sec): 1684043502.734703779
# timestamp (sec): 1684043503.014587641
# timestamp (sec): 1684043503.294746637
# timestamp (sec): 1684043503.574270248
# timestamp (sec): 1684043503.849276543
# timestamp (sec): 1684043504.135670185
# timestamp (sec): 1684043504.412160158
# timestamp (sec): 1684043504.696390390
# timestamp (sec): 1684043504.971601725
# timestamp (sec): 1684043505.251634836
# timestamp (sec): 1684043505.531780720
# timestamp (sec): 1684043505.812109470
# timestamp (sec): 1684043506.092427492
# timestamp (sec): 1684043506.372832775
# timestamp (sec): 1684043506.653466225
# timestamp (sec): 1684043506.932847500
# timestamp (sec): 1684043507.216564417
# timestamp (sec): 1684043507.489185810
# timestamp (sec): 1684043507.773962498
# timestamp (sec): 1684043508.053948879
# timestamp (sec): 1684043508.334367990
# timestamp (sec): 1684043508.614395857
# timestamp (sec): 1684043508.894433498
# timestamp (sec): 1684043509.174345732
# timestamp (sec): 1684043509.455199003
# timestamp (sec): 1684043509.724263668
so i do not know whether it is due to time.if it is true,i guess i should use the message_fliter?just like this:http://wiki.ros.org/message_filters
I want to know how can I check whether my rosbag'time is true or not?
