IMU Data with Velodyne in PCL

Question

I am using the Velodyne HDL-32E with the Velodyne grabber with GPS mouse connected to the sensor. Is there any way I can access the IMU data from the grabber or should I implement it myself?

Please share your experience.

Answer 1

I guess you are speaking about the IMU that is embedded in the Velodyne 32E (yes there is one inside!). So I do not think that having access to a GPS module will affect that (of course you could use the IMU data and the GPS data together but that is another story).

Then I am sorry but, no, you cannot use HDLGrabber from PCL to read the HDL-32E IMU.

It is also not currently implemented in ROS.

Maybe have a look at Veloview which is an open-source software developed by Kitware for Velodyne. At this line in vtkVelodyneHDLPositionReader.cxx you can see that the gyroscopic information is extracted from a data packet. There is also mention of acceleration data. You can also access this data using Veloview directly (tested using the compiled package and sample file from Velodyne): Open the .pcap file, chose "HDL-32" when the "Sensor Configuration" window opens, then open the spreadsheet with "Tools" > "Spreadsheet", then set "Showing" to "Position".

Disclamer: I am doing my internship at Kitware

Beware though that this data is "raw" and you may have some processing to do before using it as if it was coming from any commercial IMU. If that proves difficult you should consider investing in a consumer grade (10$) or industry grade IMU (1000$).