Safe Near-Optimal MDP (SNO-MDP)

This is the source-code for implementing the algorithms in the paper "Safe Reinforcement Learning in Constrained Markov Decision Processes" which was presented in ICML-20.

Installation

The easiest way is to use the Anaconda Python distribution. Then, run the following commands to install the necessary packages:

GPy and pymdptoolbox

First of all, we used GPy to implement Gaussian Processes (GPs) and pymdptoobox to calculate the optimal policy for a given Markov Decision Process (MDP).

pip install GPy
pip install pymdptoolbox

SafeMDP

Our code also heavily depends upon SafeMDP. For the installation, see the original repository.

Safety-Gym

Finally, we developed a new environment called GP-Safety-Gym. This enviornment is based on OpenAI Safety-Gym. For the installation, see Safety-Gym repository. Note that OpenAI Safety-Gym and our GP-Safety-Gym heavily depends on mujoco_py.

GP-Safety-Gym

To use our GP-Safety-Gym environment, first define an Engine_GP environment by

env = Engine_GP(config, reward_map=reward, safety_map=safety)

and render 1) the agent's position and 2) safety and reward functions by

env.discreate_move(pos)

We also provide a sample script for running GP-Safety-Gym in ./test/test_gp_safety_gym.py. In this script, the agent will target for randomly specified positions.

Synthetic Environment

Run the simulation for each method:

python main_oracle.py      # Safe/reward known
python main_sno_mdp.py     # SNO-MDP (Our proposed method, Wachi and Sui, 2020)
python main_safemdp.py     # SafeMDP (Turchetta et al., 2016)
python main_seo.py         # SafeExpOpt-MDP (Wachi et al., 2018)

For our proposed method, you can specify whether ES2/P-ES2 is leveraged, using arguments.py.

parser.add_argument('--es2-type', type=str, default='es2', 
                    choices=['es2', 'p_es2', 'none'],
                    help='whether or not ES2/P-ES2 is used')

If you would like to create a new environment and a start position, please use the following command:

python simple_make_rand_settings.py

Citation

If you find this code useful in your research, please consider citing:

@inproceedings{wachi_sui_snomdp_icml2020,
  Author = {Akifumi Wachi and Yanan Sui},
  Title = {Safe Reinforcement Learning in Constrained Markov Decision Processes},
  Booktitle  = {International Conference on Machine Learning (ICML)},
  Year = {2020}
}