Waypoint Follower

Source code on Github.

The Waypoint Follower module implements a way of doing waypoint following using the NavigateToPose action server. It will take in a set of ordered waypoints to follow and then try to navigate to them in order. It also hosts a waypoint task executor plugin which can be used to perform custom behavior at a waypoint like waiting for user instruction, taking a picture, or picking up a box. If a waypoint is not achievable, the stop_on_failure parameter will determine whether to continue to the next point or stop.

Parameters

`stop_on_failure`

Type: bool Default: true: Whether to fail action task if a single waypoint fails. If false, will continue to next waypoint.

`loop_rate`

Type: int Default: 20: Rate to check for results from current navigation task.

`global_frame_id`

Type: string Default: "map": The name of the global coordinate frame published by robot_localization. Only used by the gps_waypoint_follower to convert GPS waypoints to this frame.

`introspection_mode`

Type: string Default: "disabled": The introspection mode for services and actions. Options are "disabled", "metadata", "contents".

`bond_heartbeat_period`

Type: double Default: 0.25: The lifecycle node bond mechanism publishing period (on the /bond topic). Disabled if inferior or equal to 0.0.

`allow_parameter_qos_overrides`

Type: bool Default: true: Whether to allow QoS profiles to be overwritten with parameterized values.

`waypoint_task_executor_plugin`

Type: string Default: "wait_at_waypoint"

A plugin to define tasks to be executed when robot arrives to a waypoint.

Note

The plugin namespace defined needs to have a plugin parameter defining the type of plugin to be loaded in the namespace.

Example:

waypoint_follower:
  ros__parameters:
    waypoint_task_executor_plugin: "wait_at_waypoint"
    wait_at_waypoint:
      plugin: "nav2_waypoint_follower::WaitAtWaypoint"
      enabled: True
      waypoint_pause_duration: 0

Provided Plugins

The plugins listed below are inside the nav2_waypoint_follower namespace.

WaitAtWaypoint

Pause for a specified duration at each waypoint.

Go
PhotoAtWaypoint

Capture an image at each waypoint.

Go
InputAtWaypoint

Wait for operator input before proceeding.

Go

Default Plugin

Namespace	Plugin
"wait_at_waypoint"	"nav2_waypoint_follower::WaitAtWaypoint"

Example

waypoint_follower:
  ros__parameters:
    loop_rate: 20
    stop_on_failure: false
    waypoint_task_executor_plugin: "wait_at_waypoint"
    introspection_mode: "disabled"
      wait_at_waypoint:
        plugin: "nav2_waypoint_follower::WaitAtWaypoint"
        enabled: True
        waypoint_pause_duration: 0