Navigation Packages for DIT Robotics Eurobot 2026

This repository contains a customized navigation system based on the ROS 2 Navigation Stack (Nav2), adapted for DIT Robotics' Eurobot 2026 competition requirements.

Features

Basic Navigation

Enables smooth and efficient autonomous movement.

• Uses /nav_to_pose and /nav_thru_poses action servers for basic navigation.

Docking Integration

Seamlessly integrates docking and navigation for autonomous charging or station return.

• Utilizes the /dock_robot action server to control the docking process.

Multi-Functional Interfaces

Offers a variety of commands for enhanced control and flexibility:

• /stopRobot: Lock/unlock the robot.
• /keepout_zone: Dynamically set keepout zones to avoid certain areas.
• /dock_robot: Supports flexible keyword-based commands via the dock_type parameter.
• rival_param.yaml: Supports dynamic rival data setup adjustments.

Stop Robot

Control the robot's emergency stop or resume behavior via the /stopRobot topic.

• true: Immediately stops and locks the robot.
• false: Unlocks and resumes normal operation.
• Message Type: std_msgs/msg/Bool

Keepout Zone Index

The keepout zones correspond to specific regions on the Eurobot 2026 field, used to restrict robot access dynamically via /keepout_zone.

• Pantry zones are labeled A through J on the field map.
• Hazelnut zones are labeled K through R on the field map.
• These zones can be toggled at runtime using the /keepout_zone topic.
• Suitable for strategic behaviors like avoiding opponent areas or obstacle fields.
• Message Type: std_msgs/msg/String
• parameter settings:

global_costmap:
  global_costmap:
    ros__parameters:
      keepout_layer:
        inflation_length: 0.15   # distance over which cost is inflated
        cost_scaling_factor: 5.0   # higher value -> steeper cost increase
        keepout_expand_mode: 1   # 0: Circle, 1: Square

see more about the params /navigation2_run/params/nav2_params_default.yaml

Custom Controller: follow_path_controller

Main features:

• Look-ahead path following
  Uses a configurable look_ahead_distance to pick a look-ahead target on the global path and generate smooth velocity commands.

• Costmap-aware slowdown and replanning
  Checks cost values along the segment from current pose to a point ahead on the path.
  If any cell exceeds costmap_tolerance:

  • Scales linear velocity by speed_decade (slowdown).
  • Sets angular velocity to zero temporarily.
  • Sets update_plan_ = true to request replanning.
  • If the robot is almost stopped, throws PlannerException("Obstacle detected") so the BT can enter recovery.

• Goal yaw alignment
  Tracks the final goal yaw (final_goal_angle_).
  Uses angular_kp to scale the yaw error and clamps it with max_angular_vel_.
  Uses yaw_goal_tolerance_ to decide when the orientation is aligned.

• Rival-aware slowdown (optional)
  Computes the distance between the robot and the rival.
  When the distance is smaller than rival_slowdown_radius_, scales linear speed by rival_decay_.
  Publishes the current distance on the rival_distance topic.

• DelaySpin behavior
  When controller_function is set to "DelaySpin", in-place spinning is disabled near the start of the path.
  Spinning is only allowed after the robot moves beyond spin_delay_threshold_, then the mode automatically switches back to "None".

• Dynamic speed limiting
  Supports setSpeedLimit() to apply dynamic speed limits, either as a percentage of a base speed or as an absolute value.

Supported Keywords for /dock_robot API parameter /dock_type

(Keyword order does not matter and is designed for compatibility.)

• Template Base:

  • dock: Triggers the docking process.

• Functional Tags:

  • Controller Type: fast, slow, linearBoost, angularBoost
  • Goal Checker Type: precise, loose
  • Offset Direction: x, y, z
  • Docking Style: ordinary, gentle, rush
  • Special Control: delaySpin

Format for rival_param.yaml

rival_parameters:
  rival_inscribed_radius: *data(double)*

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How to Use

For environment setup instructions and Docker configurations, please refer to the docker/ directory.

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Repository Structure

Eurobot-2026
└── Eurobot-2026-ws/
   └── src/
      ├── Eurobot-2026-Navigation2/         # Core navigation system code
         ├── custom_bts/                     # Custom behavior trees
         ├── custom_controller/              # Custom controller plugins
         ├── custom_layer/                   # Custom costmap layers
         ├── navigation2_run/                # Navigation system packages
         ├── Navigation2/                    # Modified version of Nav2
         └── opennav_docking/                # Docking server implementation
      └── Eurobot-2026-Navigation2-envs/    # Docker environments
         ├── Navigation2-humble-local/       # Local PC environment
         └── Navigation2-humble-deploy/      # Remote machine environment

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Contribution

Contributions are welcome! Please follow these steps:

1. Fork the repository.
2. Create a feature branch.
3. Commit your changes.
4. Submit a pull request.

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License

This project is licensed under the MIT License. See the LICENSE file for details.

Portions of this software are based on the ROS 2 Navigation Stack (Nav2), which is licensed under the Apache License 2.0. See the Navigation2 submodule for more details.

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Contact

For any issues or inquiries, please open an issue on GitHub or contact the DIT Robotics team.