Voxel Layer Parameters

This costmap layer implements a plugin that uses 3D raycasting for depth, 3D, or other sensors. It contains a 3D environmental model within it that manages the planning space and squashes down to 2D for planning and control by the parameters specified below.

<voxel layer> is the corresponding plugin name selected for this type.

<data source> is the corresponding observation source name for that sources parameters.

<voxel layer>.enabled

Type	Default
bool	True

Description: Whether it is enabled.

<voxel layer>.footprint_clearing_enabled

Type	Default
bool	True

Description: Clear any occupied cells under robot footprint.

<voxel layer>.max_obstacle_height

Type	Default
double	2.0

Description: Maximum height to add return to occupancy grid.

<voxel layer>.z_voxels

Type	Default
int	10

Description: Number of voxels high to mark, maximum 16.

<voxel layer>.origin_z

Type	Default
double	0.0

Description: Where to start marking voxels (m).

<voxel layer>.z_resolution

Type	Default
double	0.2

Description: Resolution of voxels in height (m).

<voxel layer>.unknown_threshold

Type	Default
int	15

Description: Minimum number of empty voxels in a column to mark as unknown in 2D occupancy grid.

<voxel layer>.mark_threshold

Type	Default
int	0

Description: Minimum number of voxels in a column to mark as occupied in 2D occupancy grid.

<voxel layer>.combination_method

Type	Default
int	1

Description: Enum for method to add data to master costmap. Must be 0, 1 or 2, default to 1 (see below).

0 - Overwrite: Overwrite master costmap with every valid observation.

1 - Max: Sets the new value to the maximum of the master_grid’s value and this layer’s value.

This is the default.

2 - MaxWithoutUnknownOverwrite: Sets the new value to the maximum of the master_grid’s
value and this layer’s value. If the master value is NO_INFORMATION, it is NOT overwritten.
It can be used to make sure that the static map is the dominant source of information, and
prevent the robot to go through places that are not present in the static map.

<voxel layer>.publish_voxel_map

Type	Default
bool	False

Description: Whether to publish 3D voxel grid for debug, computationally expensive.

<voxel layer>.observation_sources

Type	Default
vector<string>	{“”}

Description: namespace of sources of data.

<voxel layer>. <data source>.topic

Type	Default
string	“”

Description: Topic of data.

Relative topics will be relative to the node’s parent namespace. For example, if you specify topic: scan in the voxel_layer of a local_costmap and you launch your bringup with a tb4 namespace:

User chosen namespace is tb4.
User chosen topic is scan.
Topic will be remapped to /tb4/scan without local_costmap.
Use global topic /scan if you do not wish the node namespace to apply.

<voxel layer>. <data source>.sensor_frame

Type	Default
string	“”

Description: Frame of sensor, to use if not provided by message. If empty, uses message frame_id.

<voxel layer>. <data source>.observation_persistence

Type	Default
double	0.0

Description: How long to store messages in a buffer to add to costmap before removing them (s).

<voxel layer>. <data source>.expected_update_rate

Type	Default
double	0.0

Description: Expected rate to get new data from sensor.

<voxel layer>. <data source>.data_type

Type	Default
string	“LaserScan”

Description: Data type of input, LaserScan or PointCloud2.

<voxel layer>. <data source>.min_obstacle_height

Type	Default
double	0.0

Description: Minimum height to add return to occupancy grid.

<voxel layer>. <data source>.max_obstacle_height

Type	Default
double	0.0

Description: Maximum height to add return to occupancy grid.

<voxel layer>. <data source>.inf_is_valid

Type	Default
bool	False

Description: Are infinite returns from laser scanners valid measurements to raycast.

<voxel layer>. <data source>.marking

Type	Default
bool	True

Description: Whether source should mark in costmap.

<voxel layer>. <data source>.clearing

Type	Default
bool	False

Description: Whether source should raytrace clear in costmap.

<voxel layer>. <data source>.obstacle_max_range

Type	Default
double	2.5

Description: Maximum range to mark obstacles in costmap.

<voxel layer>. <data source>.obstacle_min_range

Type	Default
double	0.0

Description: Minimum range to mark obstacles in costmap.

<voxel layer>. <data source>.raytrace_max_range

Type	Default
double	3.0

Description: Maximum range to raytrace clear obstacles from costmap.

<voxel layer>. <data source>.raytrace_min_range

Type	Default
double	0.0

Description: Minimum range to raytrace clear obstacles from costmap.