Odometry Filtered Yaw Angle in EKF Sensor Fusion
Hi
I'm using the robot localization package from ROS and I'm trying to use EKF sensor fusion to fuse multiple sensors. More specifically, I am fusing one 9-axis IMU and a ZED camera IMU. The 9-axis IMU is calibrated such that the yaw angle is pointing towards the magnetic north, while my ZED camera IMU yaw angle is relative to the camera starting position. When I fused these 2 sensors, the yaw angle from the odometry filtered (which is supposed to be more accurate) is giving me some other value. For example,
IMU yaw: 2.1119 rad ZED IMU yaw: -0.02299 rad Odom filtered yaw: -1.0297 rad
May I know where does the yaw from odom filtered comes from? If I want to make it listen to the yaw for the 9 axis IMU, how can I do that? I have tried different configurations from the EKF parameters but the results are the same. Below is my EKF config:
imu0: wit/imu imu0config: [false, false, false, true, true, true, false, false, false, false, false, true, true, true, true] imu0differential: false imu0relative: false imu0removegravitational_acceleration: true
imu1: zed/imu imu1config: [false, false, false, false, false, false, false, false, false, false, false, true, true, true, true] imu1differential: false imu1relative: false imu1removegravitational_acceleration: true
Asked by joewong00 on 2023-06-06 22:13:01 UTC
Comments
First of all, before you expect to get a more accurate reading, you should make sure that both IMU gives approximately the same yaw reading.
Second of all, according to the documentation (http://docs.ros.org/en/melodic/api/robot_localization/html/preparing_sensor_data.html), in REP-103 (https://www.ros.org/reps/rep-0103.html) defines that the IMU should be ENU frame. In other words, it should be reading 0 degrees when the imu is pointing to the east.
Third of all, what is your covariance value for your filtered yaw (should be included in the filtered odometry message). Is the covariance size large enough that covers the difference between your IMU yaw and the Odom Filtered yaw?
Asked by sdu568 on 2023-06-07 14:43:43 UTC