Closed benjaminralex closed 2 years ago
yes look good, the stamping is done in an asynchronous process, so there will be some variance, but in general the data is read by the chip @ 100-200 Hz, and any data read within the software is stamped there - if you correlate with
100-200Hz for reading of data as mentioned above, for other specs you can check out the data sheet: https://www.st.com/resource/en/datasheet/lsm9ds1.pdf
we have not worked on positioning with the imu, just orientation based on the quaternion data
Thank you so much for the information!
But how would one go about acquiring the orientation for a given image if the timestamps are asynchronous? Do the images have asynchronous time stamps as well? If so, where can they be found?
The timestamps do not correspond to a particular time point (like Epoch) but all the timestamps for all the data acquired during a particular session all have the same (arbitrary) reference therefore you can correlate the orientation data to a particular image (you might have to interpolate if there is no data for a particular timestamp).
Makes sense. I can readily find the pose timestamps but can't seem to locate the image timestamps.. which file would contain those?
The timestamps are located in the first 64 bits of each image in a raw data file, see more at: https://github.com/clariusdev/raw#raw-data-formats
Thank you! Is there a way to estimate the sensor sampling rate from the asynchronous time stamps?
I have the following questions for the attached yml:
1) Are the timestamps correct? When decoding it from posix to date/time format or when looking at the difference between time stamps, it seems to be erroneous.
2) Is there a nominal sensor frequency?
3) Does clarius provide an API or any code to extraction probe position in addition to the orientation?
Thanks imu_yml_as_text.txt !