Purpose

The messages in derived_object_msgs are meant to represent, with as much detail as possible, detected objects derived from sensor data. The contents of this package is somewhat skewed toward autonomous automotive vehicles but also contains generic messages such as Object.

Provided Message Types

In order to provide as much detail as can be provided by most sensors available today, the Object message contains:

• A detection_level to indicate whether the object has only been "detected" or whether it is "tracked" (indicating more than one detection).

• A geometry_msgs/Pose to indicate the object's estimated position and orientation.

• A geometry_msgs/Twist to represent the object's estimated linear and angular velocities.

• A geometry_msgs/Accel to indicate the object's estimated linear and angular accelerations.

• A geometry_msgs/Polygon to precisely define the detected object's estimated outer edge profile.

• A shape_msgs/SolidPrimitive to represent a shape primitive which completely encompasses the object's outer bounds (mostly for visualization).

• An object classification, if one has been determined by any of the detecting sensors.
• A classification certainty.
• A classification age.

In addition, other messages which represent real-world objects at a high level include things like Lanes, Lane Models, and Closest In-Path Vehicles.