Has anyone has seen this 'rotation' error before?

[joekeo]

I am testing the stability of some sensors and nodes in my robot, which means that i am leaving it on the spot for some while.

When the robot boots and makes the initial map, this is how it looks like: But after a while keeping the robot still, the map seems to be rotated, looking like this: Has anyone has come across this before? Any Ideas what is causing this behaviour?

[garlinplus]

how much is your yaw angle of your robot

[joekeo]

this is the .lua file:

include "map_builder.lua"
include "trajectory_builder.lua"

-- Cartographer_ros configuration reference:
-- https://google-cartographer-ros.readthedocs.io/en/latest/configuration.html

options = {
  map_builder = MAP_BUILDER,
  trajectory_builder = TRAJECTORY_BUILDER,
  map_frame = "map",
  tracking_frame = "rs_t265_accel_frame",
  published_frame = "base_link",
  use_odometry = true,
  provide_odom_frame = true,
  odom_frame = "odom",
  publish_frame_projected_to_2d = false,
  use_pose_extrapolator = on,
  use_nav_sat = false,
  use_landmarks = false,
  num_laser_scans = 1,
  num_multi_echo_laser_scans = 0,
  num_subdivisions_per_laser_scan = 1,
  num_point_clouds = 0,
  lookup_transform_timeout_sec = 0.2,
  submap_publish_period_sec = 0.3,
  pose_publish_period_sec = 5e-3,
  trajectory_publish_period_sec = 30e-3,
  rangefinder_sampling_ratio = 1.,
  odometry_sampling_ratio = 1.,
  fixed_frame_pose_sampling_ratio = 1.,
  imu_sampling_ratio = 1.,
  landmarks_sampling_ratio = 1.,
}
--tunning guide
--https://google-cartographer-ros.readthedocs.io/en/latest/tuning.html

-- Cartographer configuration options:
-- https://google-cartographer.readthedocs.io/en/latest/configuration.html

MAP_BUILDER.use_trajectory_builder_2d = true

--Local Slam
TRAJECTORY_BUILDER_2D.use_online_correlative_scan_matching = true
TRAJECTORY_BUILDER_2D.num_accumulated_range_data = 25
TRAJECTORY_BUILDER_2D.use_imu_data = true
TRAJECTORY_BUILDER_2D.min_range = 0
TRAJECTORY_BUILDER_2D.max_range = 30.
TRAJECTORY_BUILDER_2D.missing_data_ray_length = 30.1
TRAJECTORY_BUILDER_2D.max_z = .8
TRAJECTORY_BUILDER_2D.min_z = -.2

TRAJECTORY_BUILDER_2D.ceres_scan_matcher.occupied_space_weight = 1e3 --default 1
TRAJECTORY_BUILDER_2D.ceres_scan_matcher.translation_weight = 100 --defualt 10
TRAJECTORY_BUILDER_2D.ceres_scan_matcher.rotation_weight = 200 --default 40

TRAJECTORY_BUILDER_2D.motion_filter.max_time_seconds = 0.0001 --default 5.
TRAJECTORY_BUILDER_2D.imu_gravity_time_constant = 9.81 --default 10

--Optimisation parameters
TRAJECTORY_BUILDER_2D.ceres_scan_matcher.ceres_solver_options.max_num_iterations = 10
TRAJECTORY_BUILDER_2D.ceres_scan_matcher.ceres_solver_options.num_threads = 4

TRAJECTORY_BUILDER_2D.real_time_correlative_scan_matcher.linear_search_window = 0.1 --deafult 0.1
TRAJECTORY_BUILDER_2D.real_time_correlative_scan_matcher.angular_search_window = math.rad(20.) --default 20.
TRAJECTORY_BUILDER_2D.real_time_correlative_scan_matcher.translation_delta_cost_weight = 1e-1 --default 1e-1
TRAJECTORY_BUILDER_2D.real_time_correlative_scan_matcher.rotation_delta_cost_weight = 1e-1 --deafult 1e-1

TRAJECTORY_BUILDER_2D.voxel_filter_size = 0.01 --default 0.025
TRAJECTORY_BUILDER_2D.adaptive_voxel_filter.min_num_points = 50 --default 100
TRAJECTORY_BUILDER_2D.adaptive_voxel_filter.max_length = 0.5 --default 0.5
TRAJECTORY_BUILDER_2D.adaptive_voxel_filter.max_range = 50 --default 50

TRAJECTORY_BUILDER_2D.submaps.num_range_data = 20 -- default 90

--map output parameters

--Global Slam
--Setting POSE_GRAPH.optimize_every_n_nodes to 0 is a handy way
--to disable global SLAM and concentrate on the behavior of local SLAM.
--This is usually one of the first thing to do to tune Cartographer.
POSE_GRAPH.optimize_every_n_nodes = 10 --90 default

POSE_GRAPH.optimization_problem.huber_scale = 1e1 --default 1e1
POSE_GRAPH.optimization_problem.acceleration_weight = 1e3 --default 1e3
POSE_GRAPH.optimization_problem.rotation_weight = 3e5 --default 3e5
POSE_GRAPH.optimization_problem.odometry_rotation_weight = 10 --default 1e5
POSE_GRAPH.optimization_problem.odometry_translation_weight = 1 --deafult 1e5
POSE_GRAPH.optimization_problem.fixed_frame_pose_translation_weight = 1e-1 --default 1e1
POSE_GRAPH.optimization_problem.fixed_frame_pose_rotation_weight = 1e-1 --default 1e2
POSE_GRAPH.optimization_problem.local_slam_pose_translation_weight = 1e5 --default 1e5
POSE_GRAPH.optimization_problem.local_slam_pose_rotation_weight = 1e5 --default 1e5

POSE_GRAPH.constraint_builder.loop_closure_translation_weight = 1.1e5 --default 1.1e4
POSE_GRAPH.constraint_builder.loop_closure_rotation_weight = 1e6 --default 1e5
POSE_GRAPH.constraint_builder.max_constraint_distance = 30 --default 15.
POSE_GRAPH.constraint_builder.fast_correlative_scan_matcher.linear_search_window = 7. --default
POSE_GRAPH.constraint_builder.fast_correlative_scan_matcher.angular_search_window = math.rad(30.) --default math.rad(30.)
POSE_GRAPH.constraint_builder.fast_correlative_scan_matcher.branch_and_bound_depth = 7 --default 7

POSE_GRAPH.constraint_builder.ceres_scan_matcher.occupied_space_weight = 1e3 --default 20
POSE_GRAPH.constraint_builder.ceres_scan_matcher.translation_weight = 100 --default 10
POSE_GRAPH.constraint_builder.ceres_scan_matcher.rotation_weight = 200 --default 1
POSE_GRAPH.constraint_builder.ceres_scan_matcher.ceres_solver_options.num_threads = 4 --default
POSE_GRAPH.constraint_builder.ceres_scan_matcher.ceres_solver_options.max_num_iterations = 30 --default 10

POSE_GRAPH.matcher_translation_weight = 5e2 --default 5e2

POSE_GRAPH.matcher_rotation_weight = 1.6e3 --default 1.6e3

--Optimisation parameters
MAP_BUILDER.num_background_threads = 4

POSE_GRAPH.global_sampling_ratio = 0.003 --default 0.003

POSE_GRAPH.constraint_builder.sampling_ratio = 0.3 --default 0.3
POSE_GRAPH.constraint_builder.min_score = 0.55 --default 0.55

POSE_GRAPH.global_constraint_search_after_n_seconds = 10 --default 10

POSE_GRAPH.optimization_problem.ceres_solver_options.max_num_iterations = 50 --default 50
POSE_GRAPH.optimization_problem.ceres_solver_options.num_threads = 7 --default 7

return options

[nhphuong91]

I guess your IMU source for odometry is drifting quite fast. Cartographer accepts drifting in odometry data but not much. Try to use rviz to view tf between /odom and /base_link (or /base_footprint). My experience is that it would slowly and steadily rotate even though your robot is stand still.