autoware_elevation_map_loader

Purpose

This package provides elevation map for autoware_compare_map_segmentation.

Inner-workings / Algorithms

Generate elevation_map from subscribed pointcloud_map and vector_map and publish it. Save the generated elevation_map locally and load it from next time.

The elevation value of each cell is the average value of z of the points of the lowest cluster.
Cells with No elevation value can be inpainted using the values of neighboring cells.

Inputs / Outputs

Input

Name	Type	Description
input/pointcloud_map	sensor_msgs::msg::PointCloud2	The point cloud map
input/vector_map	autoware_map_msgs::msg::LaneletMapBin	(Optional) The binary data of lanelet2 map
input/pointcloud_map_metadata	autoware_map_msgs::msg::PointCloudMapMetaData	(Optional) The metadata of point cloud map

Output

Name	Type	Description
output/elevation_map	grid_map_msgs::msg::GridMap	The elevation map
output/elevation_map_cloud	sensor_msgs::msg::PointCloud2	(Optional) The point cloud generated from the value of elevation map

Service

Name	Type	Description
service/get_selected_pcd_map	autoware_map_msgs::srv::GetSelectedPointCloudMap	(Optional) service to request point cloud map. If pointcloud_map_loader uses selected pointcloud map loading via ROS 2 service, use this.

Parameters

Node Parameters

Name	Type	Description	Default	Range
map_layer_name	string	elevation_map layer name	elevation	N/A
param_file_path	string	GridMap parameters config	path_default	N/A
map_frame	string	map_frame when loading elevation_map file	map	N/A
use_sequential_load	boolean	Whether to get point cloud map by service	True	N/A
sequential_map_load_num	integer	The number of point cloud maps to load at once (only used when use_sequential_load is set true). This should not be larger than number of all point cloud map cells	1	≥1
use_inpaint	boolean	Whether to inpaint empty cells	True	N/A
inpaint_radius	float	Radius of a circular neighborhood of each point inpainted that is considered by the algorithm [m]	0.3	≥0
use_elevation_map_cloud_publisher	boolean	Whether to publish output/elevation_map_cloud	False	N/A
elevation_map_directory	string	elevation_map file (bag2)	path_default	N/A
use_lane_filter	boolean	Whether to filter elevation_map with vector_map	False	N/A
lane_margin	float	Margin distance from the lane polygon of the area to be included in the inpainting mask [m]. Used only when use_lane_filter=True	0.0	≥0

Grid Map Parameters

See: https://github.com/ANYbotics/grid_map/tree/ros2/grid_map_pcl

Name	Type	Description	Default	Range
num_processing_threads	float	Number of threads for processing grid map cells. Filtering of the raw input point cloud is not parallelized	12	≥1
min_num_points_per_cell	integer	Minimum number of points in the point cloud that have to fall within any of the grid map cells. Otherwise the cell elevation will be set to NaN	3	≥1
resolution	float	Resolution of the grid map. Width and length are computed automatically	0.3	≥0.01
height_type	integer	Resolution of the grid map. Width and length are computed automatically.	1	N/A
height_thresh	float	Height range from the smallest cluster (Only for height_type 1)	1	N/A

Point Cloud Preprocessing Parameters

Rigid body transform parameters

Rigid body transform that is applied to the point cloud before computing elevation.

Name	Type	Description	Default	Range
x	float	Translation (x) that is applied to the input point cloud before computing elevation	0	N/A
y	float	Translation (y) that is applied to the input point cloud before computing elevation	0	N/A
z	float	Translation (z) that is applied to the input point cloud before computing elevation	0	N/A
Name	Type	Description	Default	Range
--------	--------	-------------------------------------------------------------------------------------------------------------------------	-----------	--------------------
r	float	Rotation (intrinsic rotation, convention X-Y'-Z'') that is applied to the input point cloud before computing elevation.	0	≥-360.0 ≤360.0
p	float	Rotation (intrinsic rotation, convention X-Y'-Z'') that is applied to the input point cloud before computing elevation.	0	≥-360.0 ≤360.0
y	float	Rotation (intrinsic rotation, convention X-Y'-Z'') that is applied to the input point cloud before computing elevation.	0	≥-360.0 ≤360.0

Cluster Extraction Parameters

Cluster extraction is based on pcl algorithms. See https://pointclouds.org/documentation/tutorials/cluster_extraction.html for more details.

Name	Type	Description	Default	Range
cluster_tolerance	float	Distance between points below which they will still be considered part of one cluster	0.2	≥0.01
min_num_points	integer	Min number of points that a cluster needs to have (otherwise it will be discarded)	3	≥1
max_num_points	integer	Max number of points that a cluster can have (otherwise it will be discarded)	1e+06	N/A

Outlier Removal Parameters

See https://pointclouds.org/documentation/tutorials/statistical_outlier.html for more explanation on outlier removal.

Name	Type	Description	Default	Range
is_remove_outliers	boolean	Whether to perform statistical outlier removal	0	N/A
mean_K	float	Number of neighbors to analyze for estimating statistics of a point	10	≥1
stddev_threshold	float	Number of standard deviations under which points are considered to be inliers	1	N/A

Subsampling Parameters

See https://pointclouds.org/documentation/tutorials/voxel_grid.html for more explanation on point cloud downsampling.

Name	Type	Description	Default	Range
is_downsample_cloud	boolean	Whether to perform downsampling or not	False	N/A
Name	Type	Description	Default	Range
--------	--------	-------------------------	-----------	---------
x	float	Voxel size(x) in meters	0.02	≥0.001
y	float	Voxel size(y) in meters	0.02	≥0.001
z	float	Voxel size(z) in meters	0.02	≥0.001