Configuration

note

If you are using a physical robot you must integrate the 2D lidar and IMU. This includes ensuring robot.yaml is configured as described below as well as ensuring the sensors are mechanically mounted and have all necessary power/USB/ethernet cables connected.

Configuring robot.yaml

The robot configuration file robot.yaml must be set up to include a 2D laser scanner and an IMU by adding the sensors.lidar2d and sensors.imu fields. For this example we will use a Husky A300 with the standard Phidgets IMU and a Hokuyo UST sensor.

The following is the sample robot.yaml file used for this tutorial:

serial_number: a300-0000
version: 0
system:
  hosts:
    - hostname: a300-0000
      ip: 127.0.0.1
  ros2:
    namespace: a300_0000
#  workspaces:
#    - /path/to/my/workspace/install/setup.bash
platform:
  enable_ekf: true
  controller: ps4
  attachments:
    - name: front_bumper
      type: a300.bumper
      parent: front_bumper_mount
    - name: rear_bumper
      type: a300.bumper
      parent: rear_bumper_mount
    - name: top_plate
      type: a300.top_plate
sensors:
  imu:
    - model: phidgets_spatial
      urdf_enabled: true
      launch_enabled: true
      parent: base_link
      xyz: [0.059, 0.0, 0.161275]
      rpy: [0.0, 0.0, 0.0]
      ros_parameters:
        phidgets_spatial:
          data_interval_ms: 20
  lidar2d:
    - model: hokuyo_ust
      parent: default_mount

Modifying Navigation Parameters

The clearpath_nav2_demos package contains default configurations for all supported platforms:

• Husky A300 and A200;
• Jackal J100;
• Dingo DO100, DO150, DD100, and DD150;
• Ridgeback R100; and
• Warthog W200. If you need to modify the nav2, slam or localization parameters you can use the configuration extras to override the default parameters included in the clearpath_nav2_demos package. For example, if your robot has additional attachments that extend beyond the normal footprint of the robot you can resize the footprint:

platform:
  extras:
    ros_parameters:
      local_costmap:
        footprint: "[ [0.495, 0.349], [0.495, -0.349], [-0.600, -0.349], [-0.600, 0.349] ]"
      global_costmap:
        footprint: "[ [0.495, 0.349], [0.495, -0.349], [-0.600, -0.349], [-0.600, 0.349] ]"

In this example, the rear of the footprint has been extended from -0.495 to -0.600, representing some extension or attachment that extends out the back of the robot.

tip

The default parameters should only be modified if necessary; if you do not have a specific need to change the defaults, we strongly advise not modifying them.