front_vehicle_velocity_estimator

This package contains a front vehicle velocity estimation for offline perception module analysis. This package can:

• Attach velocity to 3D detections from velocity estimation with LiDAR pointcloud.

Algorithm

• Processing flow
  1. Choose front vehicle from front area objects.
  2. Choose nearest neighbor point within front vehicle.
  3. Estimate velocity of front vehicle by using the differentiated value from time series of nearest neighbor point positions.
  4. Compensate ego vehicle twist

Input

Name	Type	Description
~/input/objects	autoware_auto_perception_msgs/msg/DetectedObject.msg	3D detected objects.
~/input/pointcloud	sensor_msgs/msg/PointCloud2.msg	LiDAR pointcloud.
~/input/odometry	nav_msgs::msg::Odometry.msg	Odometry data.

Output

Name	Type	Description
~/output/objects	autoware_auto_perception_msgs/msg/DetectedObjects.msg	3D detected object with twist.
~/debug/nearest_neighbor_pointcloud	sensor_msgs/msg/PointCloud2.msg	The pointcloud msg of nearest neighbor point.

Node parameter

Name	Type	Description	Default value
update_rate_hz	double	The update rate [hz].	10.0

Core parameter

Name	Type	Description	Default value
moving_average_num	int	The moving average number for velocity estimation.	1
threshold_pointcloud_z_high	float	The threshold for z position value of point when choosing nearest neighbor point within front vehicle [m]. If z > threshold_pointcloud_z_high, the point is considered to noise.	1.0f
threshold_pointcloud_z_low	float	The threshold for z position value of point when choosing nearest neighbor point within front vehicle [m]. If z < threshold_pointcloud_z_low, the point is considered to noise like ground.	0.6f
threshold_relative_velocity	double	The threshold for min and max of estimated relative velocity ($v_{re}$) [m/s]. If $v_{re}$ < - threshold_relative_velocity , then $v_{re}$ = - threshold_relative_velocity. If $v_{re}$ > threshold_relative_velocity, then $v_{re}$ = threshold_relative_velocity.	10.0
threshold_absolute_velocity	double	The threshold for max of estimated absolute velocity ($v_{ae}$) [m/s]. If $v_{ae}$ > threshold_absolute_velocity, then $v_{ae}$ = threshold_absolute_velocity.	20.0