Introduction

This repo provides OpenAI Gym-compatible environments for traffic light control scenarios and a bunch of baseline methods.

Environments include single intersections (single-agent) and multi-intersections (multi-agents) with different road networks and traffic flow settings.

Baselines include traditional Traffic Signal Control algorithms and reinforcement learning-based methods.

LibSignal is a cross-simulator environment that provides multiple traditional and Reinforcement Learning models in traffic control tasks. Currently, we support SUMO, CityFlow, and CBEine simulation environments. Conversion between SUMO and CityFlow is carefully calibrated.

Install

Source

LibSignal provides installation from the source code. Please execute the following command to install and configure our environment.

mkdir DaRL
cd DaRL
git clone git@github.com:DaRL-LibSignal/LibSignal.git

Simulator environment configuration

Though CityFlow and SUMO are stable under Windows and Linux systems, we still recommend users work under the Linux system. Currently, CBEngine is stable under the Linux system.

CityFlow Environment

To install CityFlow simulator, please follow the instructions on CityFlow Doc

sudo apt update && sudo apt install -y build-essential cmake

git clone https://github.com/cityflow-project/CityFlow.git
cd CityFlow
pip install .

To test configuration:

import cityflow
env = cityflow.Engine

SUMO Environment

To install SUMO environment, please follow the instructions on SUMO Doc

sudo apt-get install cmake python g++ libxerces-c-dev libfox-1.6-dev libgdal-dev libproj-dev libgl2ps-dev swig

git clone --recursive https://github.com/eclipse/sumo

export SUMO_HOME="$PWD/sumo"
mkdir sumo/build/cmake-build && cd sumo/build/cmake-build
cmake ../..
make -j$(nproc)

To test installation:

cd ~/DaRL/sumo/bin
./sumo

To add SUMO and traci model into the system PATH, execute the code below:

export SUMO_HOME=~/DaRL/sumo
export PYTHONPATH="$SUMO_HOME/tools:$PYTHONPATH"

To test configuration:

import libsumo
import traci

CBEngine

CBEngine currently works stably under the Linux system; we highly recommend users choose Linux if we plan to conduct experiments under the CBEinge simulation environment. (Currently not available)

Converter

We provide a converter to transform configurations including road net and traffic flow files across CityFlow and SUMO. More details in converter.py

To convert from CityFlow to SUMO:


python converter.py --typ c2s --or_cityflownet CityFlowNetPath --sumonet ConvertedSUMONetPath --or_cityflowtraffic CityFlowTrafficPath --sumotraffic ConvertedSUMOTrafficPath

To convert from SUMO to CityFlow:

python converter.py --typ s2c --or_sumonet SUMONetPath --cityflownet ConvertedCityFlowNetPath --or_sumotraffic SUMOTrafficPath --cityflowtraffic ConvertedCityFlowTrafficPath --sumocfg SUMOConfigs

After running the code, the converted traffic network files, traffic flow files, and some intermediate files will be generated in the specified folder.

Requirement

Our code is based on Python version 3.9 and Pytorch version 1.11.0. For example, if your CUDA version is 11.3 you can follow the instructions on PyTorch

pip3 install torch torchvision torchaudio --extra-index-url https://download.pytorch.org/whl/cu113

pip install -r requirements.txt

Selective agents

We also support agents implemented based on other libraries

# Colight Geometric implementation based on default environment mentioned in Requirement

pip install torch-scatter torch-sparse torch-cluster torch-spline-conv torch-geometric -f https://data.pyg.org/whl/torch-1.11.0+cu113.html

# ppo_pfrl implementation
pip install pfrl

Detailed instructions can be found on page Pytorch_geometric and PFRL. After installation, user should uncomment code in PATH ./agent/__init__.py

# from .ppo_pfrl import IPPO_pfrl
# from colight import CoLightAgent

Start

Run Model Pipeline

Our library has a uniform structure that empowers users to start their experiments with just one click. Users can start an experiment by setting arguments in the run.py file and start with their customized settings. The following part is the arguments provided to customize.

python run.py

Supporting parameters:

thread_num: number of threads for cityflow simulation
ngpu: how many gpu resources used in this experiment
task: task type to run
agent: agent type of agents in RL environment
world: simulator type
dataset: type of dataset in training process
path: path to configuration file
prefix: the number of predix in this running process
seed: seed for pytorch backend

Maintaining plan

To ensure the stability of our traffic signal testbed, we will first push new code onto dev branch, after validation, then merge it into the master branch.

UPdate index	Date	Status	Merged
MPLight implementation	July-18-2022	developed	√
Libsumo integration	August-8-2022	developed	√
Delay calculation	August-8-2022	developed	√
CoLight adaptation for heterogenous network	September-1-2022	developling
Optimize FRAP and MPLight	October-4-2022	developed	√
FRAP adaptation for irregular intersections	October-18-2022	developed	√
PettingZoo envrionment to better support MARL	Jul-18-2023	developed
RLFX Agent controlling phase and duration	Jul-18-2023	developed
Ray rllib support	Jul-18-2023	developling

Citation

LibSignal is accepted by the Machine Learning Journal by Springer: Mei, H., Lei, X., Da, L. et al. Libsignal: an open library for traffic signal control. Mach Learn (2023). https://doi.org/10.1007/s10994-023-06412-y and can be cited with the following BibTeX entry (A short version is accepted by NeurIPS 2022 Workshop: Reinforcement Learning for Real Life):

@article{mei2023libsignal,
  title={Libsignal: an open library for traffic signal control},
  author={Mei, Hao and Lei, Xiaoliang and Da, Longchao and Shi, Bin and Wei, Hua},
  journal={Machine Learning},
  pages={1--37},
  year={2023},
  publisher={Springer}
}

ldfrancis/LibSignal