bot_navigation

bot_navigation – Autonomous Navigation Stack

Autonomous navigation package built on ROS 2 Navigation2 (Nav2). This package provides path planning, obstacle avoidance, and goal-directed autonomous navigation for the BotBrain robot platform.

Purpose

The bot_navigation package enables autonomous robot navigation by integrating the Nav2 stack with the BotBrain system. It manages:

• Global path planning
• Local trajectory planning and obstacle avoidance
• Behavior coordination (recovery behaviors, waypoint following)
• Velocity command generation for autonomous motion
• Integration with localization and mapping systems
• Runtime utilities for interacting with Nav2 actions

Package Files

Launch Files

launch/nav2.launch.py

Main Nav2 launcher that starts all componets:

Nodes Launched:

1. controller_server – Executes planned paths and generates velocity commands
2. smoother_server – Smooths planned paths
3. planner_server – Computes global paths
4. behavior_server – Handles recovery behaviors (backup, spin, wait)
5. bt_navigator – Behavior Tree–based navigation coordinator
6. waypoint_follower – Executes waypoint navigation

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launch/nav_utils.launch.py

Launches auxiliary navigation utility nodes.

Nodes Launched:

• nav2_utils – Lifecycle node providing runtime services for Nav2 interaction

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launch/navigation.launch.py

High-level launcher that composes the navigation stack.

Includes:

• nav_utils.launch.py
• nav2.launch.py

This is the recommended entry point for starting navigation.

Usage:

ros2 launch bot_navigation navigation.launch.py

Navigation Utilities

scripts/nav2_utils.py

Lifecycle node that exposes a service interface for interacting with Nav2 actions.

Features:

• Provides the /cancel_nav2_goal service (std_srvs/Trigger)
• Cancels active Nav2 goals for:
  • NavigateToPose
  • FollowWaypoints
• Designed to run alongside Nav2 using a multi-threaded executor
• Namespaced automatically using robot_name from robot_config.yaml

Use case examples:

• Emergency stop or external cancellation of navigation goals
• Integration with higher-level behavior or safety systems

Robot-Specific Configuration

Each robot package provides tuned navigation parameters:

• go2_pkg/config/nav2_params.yaml – Unitree Go2
• tita_pkg/config/nav2_params.yaml – Tita quadruped
• g1_pkg/config/nav2_params.yaml – G1 humanoid

Parameters include:

• Robot footprint and collision geometry
• Kinematic limits (velocity, acceleration)
• Controller tuning
• Costmap layer configuration

Integration with Robot System

Required Components

Navigation requires the following BotBrain packages:

1. Localization (bot_localization) – Provides map frame and robot pose
2. Description (bot_description) – Provides robot model and TF tree
3. Twist Mux (bot_bringup) – Multiplexes navigation commands with other motion sources

Directory Structure

bot_navigation/
├── bot_navigation/
│   └── __init__.py
├── launch/
│   ├── nav2.launch.py              # Main Nav2 launcher
│   ├── nav_utils.launch.py         # Nav2 utilities launcher
│   └── navigation.launch.py        # High-level navigation launcher
├── scripts/
│   └── nav2_utils.py               # Nav2 utility lifecycle node
├── CMakeLists.txt
├── package.xml
└── README.md

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