TRAVEL: Pointcloud Ground Segmentation

Original algorithm: https://github.com/url-kaist/TRAVEL

I wanted to use this ground segmentation in a python repository and so I converted the C++ functions to python apis. I use Open3D to interface with the function (see travel_demo.py for usage).

Note that this only does the ground segmentation part of TRAVEL, not the object clustering.

Additional changes: Modified the estimateGround function to return ground_inds, rather than the separated ground and obj pcd to allow for indexing the original input pointcloud and retaining extra channel information.

Pre-Requisites

Apt libraries:

apt update && apt install libeigen3-dev libflann-dev libglu1-mesa-dev freeglut3-dev mesa-common-dev libboost1.65-dev

Download BOOST lib (https://www.boost.org/doc/libs/1_65_1/more/getting_started/unix-variants.html)

wget https://boostorg.jfrog.io/artifactory/main/release/1.65.1/source/boost_1_65_1.tar.gz
tar -xvf boost_1_65_1.tar.gz
cd boost_1_65_1 && ./bootstrap.sh # Downloads boost to /usr/local
./b2 install

Download pcl-1.8 library (https://pcl.readthedocs.io/projects/tutorials/en/latest/compiling_pcl_posix.html)

wget https://github.com/PointCloudLibrary/pcl/archive/refs/tags/pcl-1.8.0.tar.gz
tar -xvf pcl-1.8.0.tar.gz
cd pcl-1.8.0 && mkdir build && cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
make -j2
make -j2 install

Change the path of pcl-1.8 based on where it installs to. Default is: "/usr/local/include/pcl-1.8/"

To include in any project, structure the files like this:

my_project
- travel
  - travel_api.py 
  - src
    - tgs.hpp
    - travel_pybind.cpp
  

Then in the setup.py file,

ext_modules=[
        Pybind11Extension(
            name='travel.ground_seg', 
            sources=['travel/src/travel_pybind.cpp'],
            include_dirs=[
            os.environ.get("EIGEN_INCLUDE_DIR", "/usr/include/eigen3/"),
            "/usr/local/include/pcl-1.8/"],          
            extra_compile_args=['-std=c++14'],
            ), 
            ...OtherExtensions...]

Troubleshooting

If the above doesn't work, a dirty workaround is to keep this repo's setup.py in the travel folder and build it from there.

my_project
- travel
  - travel_api.py 
  - setup.py
  - src
    - tgs.hpp
    - travel_pybind.cpp

Building with either python setup.py develop or pip install -e . --user should work.

How to run

Run docker. Note that python in my provided docker image needs to run with python3.7 i.e. python3.7 travel_demo.py

bash docker/run.sh

Running TRAVEL in python

python setup.py develop
python travel_demo.py

Running TRAVEL in cpp (without ROS)

Build files

mkdir build && cd build
cmake ..
make

Run the program with

./travel