ROS and Mountain Car Dynamics Simulator

Project Description

This project aims to simulate a mountain car scenario within the ROS/Gazebo simulation environment. It focuses on developing a simulation where a car must navigate up a steep hill, incorporating elements such as varying landscape height, friction, kinetic energy, and simple control mechanisms to accurately represent the dynamics of a mountain car.

Contributors

• Professor: Dr. Richard B. Sowers
• Student Researcher: Jaime Jarauta Gastelu

Installation Requirements

• ROS Noetic
• Gazebo 11

Documentation

For further details and documentation, visit here.

Repository Overview

ROS_V1: Initial Version

• Hill/Model: STL model of the V1 hill, including an Excel workbook of formulas used.
• Other Worlds: Original ROS package attempt to create a pub/sub network (not functional) and other worlds. my_mesh.world includes the hill object.
• cartest.py: Original Python script provided.
• gazebo-11 files: Standard Gazebo files and some additional models.

How to Run

roscore
cd ~/catkin_ws/
# Open a new terminal
source devel/setup.bash
rosrun car_test talker.py

ROS_V2: Controlled Differential Car

• Incorporates a differential car controllable via terminal using twist.teleop.
• diff_drive_ws: Contains the latest and functional ROS package for the controlled car.

How to Run

cd diffDrive_ws
catkin_make
# Open a new terminal
source devel/setup.bash
roslaunch simulation_environment diff_drive.launch
# Open a new terminal
rosrun teleop_twist_keyboard teleop_twist_keyboard.py
# Optional
rostopic list

ROS_V3: Automated Movement and ML Controls

Focuses on automating the movement process and applying ML controls to the car.

ROS_V3.1

• Launches an empty Gazebo world; running the Python script moves the car to a pre-determined (x,y) position.

ROS_V3.2

• Launches a Gazebo world with the hill file; runs the same Python script as ROS_V3.1 considering gravity, mass, and other parameters.

ROS_V3.3

• Includes a Python script applying forward/backward acceleration based on the car's movement direction.
• Includes as well a simple PID control in order to prevent the car from turning as it reaches speeds close to zero.
• Available in two versions:
  • catkin_ws_flat: Runs the script without the hill to observe linear speed changes without external perturbations.
  • catkin_ws: Runs the script with the hill.

ROS_V3.4

• Includes a new profile which represents better the mountain in the ML policies video

• Includes a flag to the destination point

• Includes 3 different policies

  • Policy 1: applies force only when to the right of the hill and positive velocity
  • Policy 2: applies positive force when robot has positive velocity
  • Policy 3: applies positive force when robot has positive velocity, and negative force when negative velocity

• Available in two versions:

  • catkin_ws_big: has the big mountain profile as the hill
  • catkin_ws: has the small mountain profile as the hill (0.25 scale in z axis)
  • catkin_ws_flat: moves the robot in a flat surface

ROS_V3.5

• In progress
• Tries to simulate gusts of wind
• Tries to include change of color of car depending on forward/backward acceleration

models

• Folder of the models and the necessary files to run them used in all simulations (ROS V1-V3)
• Types of files used - .obj .stl .dae .material .jpg/.png

How to Run (for each version, open each line in a new terminal window)

cd ~/catkin_ws # or cd ~/catkin_ws_flat for the flat version
roscore

source devel/setup.bash
roslaunch car_test car.launch

# If you want to see the linear speed values
source devel/setup.bash
rostopic echo /car/diff_drive_controller/odom/twist/twist

# If you want to see the robot's position values
source devel/setup.bash
rosrun car_test car_position_listener.py

# To run the python policy scripts
source devel/setup.bash
rosrun car_test code_PX.py # code_P1.py - code_P2.py - code_P3.py

REMEMBER TO INLCUDE THE MODELS FOLDER IN /usr/share/gazebo-11/ DIRECTORY