map alignment

[ppxsky]

Hi, thanks for your work! I have been actively testing your package on my robot and i have 2 observations i would appreciate any help for:

1. During turns i notice the alignment drifts quite a bit, it does end up aligning itself fine once turn in the map is over, but its still happens
2. When the robot is stationary the pose jitters in its spot quite a bit, this is observed throught the run.

The parameters i am using is this. Any help tuning these parameters to mitigate my issue is appreciated.

/**:
    ros__parameters:
      registration_method: "NDT_OMP"
      score_threshold: 2.0
      ndt_resolution: 1.0
      ndt_step_size: 0.1
      ndt_num_threads: 4
      ndt_max_iterations: 35
      transform_epsilon: 0.01
      voxel_leaf_size: 0.05
      scan_max_range: 80.0
      scan_min_range: 1.0
      scan_period: 0.1
      set_initial_pose: true
      initial_pose_x: 0.0
      initial_pose_y: 0.0
      initial_pose_z: 0.0
      initial_pose_qx: 0.0
      initial_pose_qy: 0.0
      initial_pose_qz: 0.0
      initial_pose_qw: 1.0
      use_odom: true
      use_imu: false
      global_frame_id: "map"
      odom_frame_id: "odom"
      base_frame_id: "base_link"
      enable_debug: false
      enable_map_odom_tf: false

[Zeynepqq]

I'm experiencing the same problem. Were you able to solve it?

[rsasaki0109]

Sorry, I hadn’t gotten back to you.

Hmm… this seems more like an implementation issue rather than a parameter-tuning problem.
For rotations, it would likely be necessary to compensate the orientation using an IMU, and for the stationary jitter, applying filtering such as a Kalman filter would probably be required.