Hebi Robot Description

This repository contains the ROS package hebi_description (folder name hebi_robot), which provides the robot description, simulation configurations, and control scripts for the Hebi robot. The robot is a quadruped with wheels on its legs (hybrid locomotion).

Table of Contents

• Prerequisites
• Installation
• Usage
• Launch Files
• Control
• Project Structure
• Maintainers

Prerequisites

• OS: Ubuntu 18.04 (Bionic) or 20.04 (Noetic)
• ROS: Melodic (for Ubuntu 18.04) or Noetic (for Ubuntu 20.04)
• Python: Python 3.x

Installation

A convenient installation script is provided to set up the environment and dependencies.

1. Run the installation script

# For Ubuntu 18.04
./loco-install.sh 18

# For Ubuntu 20.04
./loco-install.sh 20

Options:

• -r: Install RealSense camera dependencies.
• -g: Install Graspin dependencies.

Example with RealSense support:

./loco-install.sh 20 -r

This script will:

• Install system dependencies (ROS, Robotpkg, Python libs).
• Setup ROS sources if not present.
• Install the required ROS packages.

Usage

Using the Run Script

You can use the provided loco-run.sh script to build and run the controller.

./loco-run.sh <package_name> <controller_name> [-i]

Example:

./loco-run.sh hebi_robot hebi_controller.py

Note: This script attempts to copy controller files from a controller directory and run them. Ensure your paths are correct.

Manual Execution

1. Launch Gazebo/RViz:

   roslaunch hebi_robot gazebo.launch

2. Run the Controller: Ensure required dependency locosim is in your PYTHONPATH or workspace.

   python3 scripts/hebi_controller.py

Launch Files

The launch/ directory contains several launch configurations:

• gazebo.launch: Launches the robot in the Gazebo simulator.
• simple_walk.launch: Launches a walking demo (requires simple_walk.py).
• visualize.launch: Launches RViz for visualization.
• upload.launch: Uploads the robot description (URDF/Xacro) to the ROS parameter server.
• world.launch: Launches the Gazebo world.

Control

The robot features a Pygame-based control interface (window must be focused).

Key Bindings

Movement:

• UP / W: Increase Forward Speed
• DOWN / S: Decrease Forward Speed (Reverse)
• LEFT / A: Rotate Left
• RIGHT / D: Rotate Right
• SPACE: Stop (if not implemented, release keys usually decays speed)

Control Parameters (Gains & Height):

• H / L: Increase / Decrease Height Kp ($K_{p_h}$)
• B / M: Increase / Decrease Height Kd ($K_{d_h}$)
• R / T: Increase / Decrease Orientation Kp ($K_{p_w}$)
• F / G: Increase / Decrease Orientation Kd ($K_{d_w}$)
• Y / U: Increase / Decrease Desired Height ($h_{des}$)

Toggles:

• 1: Lock Speed
• 2: Lock Rotation
• P: Toggle Snapshot Request

Project Structure

hebi_robot/
├── launch/             # ROS launch files
├── scripts/            # Python control scripts
│   ├── hebi_controller.py  # Main controller implementation
│   ├── pygame_controls.py  # Keyboard/Joystick interface
│   └── params.py           # Robot parameters
├── urdf/               # Robot description (Xacro/URDF)
├── meshes/             # 3D models for the robot
├── worlds/             # Gazebo world files
├── loco-install.sh     # Installation script
├── loco-run.sh         # Execution script
├── package.xml         # ROS package metadata
└── CMakeLists.txt      # Build configuration

Maintainers

• Alejandro Barbi
• Alessandro Moscatelli
• Elia Avanzolini