BRICK IMU V2 - Heading issue

[RodolphePerrin]

Hi,

 

I'm currently using the IMU V2 Brick for a mobile robot application.

 

I fixed the IMU on the robot and connected it via USB to the computer. Now, If I turn the robot at a reasonable speed for a 360 turn, I can see the IMU being accurate (when coming back to initial position, the IMU heading goes back to its expected value on the Brick Viewer). However,if I turn slower, I can clearly see that at some point the Euler/Quaternion calculation seems to "freeze" until I stop the machine back at initial heading position. Then, the IMU starts to correct itself but the correction is always wrong (it can be even wrong by more than 100 degrees).

 

When I connect the IMU to a ROS node topic that publishes the imu data, I can see the same problem. I tried to used all 4 sensor fusion mode to change that but I can't seem to understand where the problem is coming from. This error can cause bad localization and mapping.

 

Do you have any idea where this could come from or what parameters could be changed to remove it and increase heading accuracy ?

 

The IMU firmware has been updated to 2.0.13.

 

Thanks so much !