locomotor_msgs

This class provides the NavigateToPose action for use with actionlib+locomotor. The idea is to provide more useful feedback than MoveBase.action.

Developers are encouraged to define their own actions that have statistics/constraints relative to their own domains.

Progress City

The percent_complete field in the NavigateToPoseFeedback is provided as a convenience, and is equivalent to distance_traveled / (distance_traveled + estimated_distance_remaining). Note that with the current implementation, it is possible for percent_complete to go down if the estimated_distance_remaining goes up, which can happen when the global plan is blocked and a new longer global plan is found instead.

I Want Results!

When the action finishes, the action client can figure out whether the action succeeded by checking if the state is SUCCEEDED or ABORTED. The SimpleActionServer/Client also provides “an optional text message”. While these two fields may provide sufficient information about the final state of the action, we provide one other method for providing final feedback.

The NavigateToPoseResult contains a ResultCode message, which contains the integer field result_code and some enums for possible values of result_code.

These Exception Codes are Based on

1. Which of the four components (Global/Local Costmap, Global/Local Planner) the error originates from
2. The particular exception thrown, based on the exception hierarchy defined in nav_core2/exceptions.h

These particular result codes are used in conjunction with the StateMachines defined in the locomotor package, but other user-implemented StateMachines could use different custom-error codes, or build onto the existing error codes, as some space is left between the existing enum values.