ME495 Embedded Systems Homework 2

Author: Asa Rogers

This package, turtle_brick, simulates a turtle robot that interacts with an arena and brick within the ROS 2 environment. The turtle attempts to catch a falling brick by coordinating its movements in the arena based on physics and real-time positioning. The simulation utilizes RViz for visualization and integrates a variety of ROS 2 services and messages to control the turtle's actions and the environment.

Quickstart

1. Launch the Simulation:

   • Use the following command to launch the arena and turtle simulation:

     colcon clean workspace -y && colcon build && source install/setup.bash && ros2 launch turtle_brick show_turtle.launch.py

   • This will start the turtle simulation in the RViz environment, along with the arena, catcher, and turtle_robot nodes.

2. Place the brick:

   • Use this command to place the brick in the arena at a x, y, z position:

     source install/setup.bash && ros2 service call /place turtle_brick_interfaces/srv/Place "{x: 5.0, y: 1.0, z: 10.0}" 

3. Drop the Brick:

   • Use this command to drop the brick:

     ros2 service call /drop std_srvs/srv/Empty

   • This initiates the brick’s descent, which the turtle will attempt to catch if it is within reachable range.

4. Videos:

   • Here are videos demonstrating the turtle's behavior under different scenarios:

     • Brick within Catching Range:

Screencast.from.2024-10-31.14-14-26.online-video-cutter.com.mp4

 - **Brick Out of Reach**: 

Screencast.from.2024-10-31.14-15-44.online-video-cutter.com.mp4

Functionality Overview

The package defines nodes and services as follows:

• Arena (arena node): Initializes the arena environment in RViz, including walls and a platform. It also provides services for placing, dropping, and stopping the brick’s gravity to simulate sticking on the turtle platform.

• Catcher (catcher node): Controls the turtle’s movements to attempt catching the brick. It calculates reachability based on brick and turtle positions and uses the stop_gravity service to catch the brick if reachable.

• Turtle Robot (turtle_robot node): Manages turtle robot simulation within the arena, handling dynamic frames, transformations, and velocities for movement control.