Lie-Group-for-Robotics

This repository provides a small C++ library implementing Lie group and Lie algebra utilities commonly used in robotics. The library comes with a simple differential drive example demonstrating how the components fit together.

Please feel free to report any bugs and suggest improvements!

Requirements

• C++17 compatible compiler (e.g. g++)
• Eigen3 (>= 3.4)
• nlohmann/json
• CMake >= 3.10
• Python 3 (optional, for plotting the example results)

On Ubuntu the required packages can be installed with:

sudo apt-get install cmake g++ libeigen3-dev nlohmann-json3-dev python3 python3-pip

Building

Create a build directory and compile the library and example:

mkdir build
cd build
cmake ..
make

This builds the shared library liblie_lib and the example executable demo_lie_lib.

Running the Example

From the build directory run:

./demo_lie_lib

The program reads parameters from diffdrive_example/diffdrive.json and writes a trajectory to diffdrive_example/robot_pos.json.

To plot the resulting path with Python:

python3 ../diffdrive_example/plot.py

Edit the file diffdrive_example/plot.py if your paths differ.

Repository Layout

• include/lie_lib – Header files for the Lie group utilities
• src/ – Implementation files
• diffdrive_example/ – Simple differential drive demo and plotting script
• CMakeLists.txt – Build configuration