Skip to content

PyBullet CartPole and Quadrotor environments—with CasADi symbolic a priori dynamics—for learning-based control and RL

License

Notifications You must be signed in to change notification settings

utiasDSL/safe-control-gym

Repository files navigation

safe-control-gym

Physics-based CartPole and Quadrotor Gym environments (using PyBullet) with symbolic a priori dynamics (using CasADi) for learning-based control, and model-free and model-based reinforcement learning (RL).

These environments include (and evaluate) symbolic safety constraints and implement input, parameter, and dynamics disturbances to test the robustness and generalizability of control approaches. [PDF]

problem illustration

@article{brunke2021safe,
         title={Safe Learning in Robotics: From Learning-Based Control to Safe Reinforcement Learning},
         author={Lukas Brunke and Melissa Greeff and Adam W. Hall and Zhaocong Yuan and Siqi Zhou and Jacopo Panerati and Angela P. Schoellig},
         journal = {Annual Review of Control, Robotics, and Autonomous Systems},
         year={2021},
         url = {https://arxiv.org/abs/2108.06266}}

To reproduce the results in the article, see branch ar.

@article{yuan2021safecontrolgym,
  author={Yuan, Zhaocong and Hall, Adam W. and Zhou, Siqi and Brunke, Lukas and Greeff, Melissa and Panerati, Jacopo and Schoellig, Angela P.},
  journal={IEEE Robotics and Automation Letters},
  title={Safe-Control-Gym: A Unified Benchmark Suite for Safe Learning-Based Control and Reinforcement Learning in Robotics},
  year={2022},
  volume={7},
  number={4},
  pages={11142-11149},
  doi={10.1109/LRA.2022.3196132}}

To reproduce the results in the article, see branch submission.

Install on Ubuntu/macOS

Clone repo

git clone https://github.com/utiasDSL/safe-control-gym.git
cd safe-control-gym

(optional) Create a conda environment

Create and access a Python 3.10 environment using conda

conda create -n safe python=3.10
conda activate safe

Install

Install the safe-control-gym repository

python -m pip install --upgrade pip
python -m pip install -e .

Note

You may need to separately install gmp, a dependency of pycddlib:

conda install -c anaconda gmp

or

sudo apt-get install libgmp-dev

(optional) Additional requirements for MPC

You may need to separately install acados for fast MPC implementations.

Architecture

Overview of safe-control-gym's API:

block diagram

Configuration

config

Getting Started

Familiarize with APIs and environments with the scripts in examples/

3D Quadrotor Lemniscate Trajectory Tracking with PID

cd ./examples/   # Navigate to the examples folder
python3 pid/pid_experiment.py \
    --algo pid \
    --task quadrotor \
    --overrides \
        ./pid/config_overrides/quadrotor_3D/quadrotor_3D_tracking.yaml

systems trajectory

Cartpole Stabilization with LQR

cd ./examples/   # Navigate to the examples folder
python3 lqr/lqr_experiment.py \
    --algo lqr \
    --task cartpole \
    --overrides \
        ./lqr/config_overrides/cartpole/cartpole_stabilization.yaml \
        ./lqr/config_overrides/cartpole/lqr_cartpole_stabilization.yaml

2D Quadrotor Trajectory Tracking with PPO

cd ./examples/rl/   # Navigate to the RL examples folder
python3 rl_experiment.py \
    --algo ppo \
    --task quadrotor \
    --overrides \
        ./config_overrides/quadrotor_2D/quadrotor_2D_track.yaml \
        ./config_overrides/quadrotor_2D/ppo_quadrotor_2D.yaml \
    --kv_overrides \
        algo_config.training=False

Verbose API Example

cd ./examples/   # Navigate to the examples folder
python3 no_controller/verbose_api.py \
    --task cartpole \
    --overrides no_controller/verbose_api.yaml

List of Implemented Controllers

List of Implemented Safety Filters

Performance

We compare the sample efficiency of safe-control-gym with the original OpenAI Cartpole and PyBullet Gym's Inverted Pendulum, as well as gym-pybullet-drones. We choose the default physic simulation integration step of each project. We report performance results for open-loop, random action inputs. Note that the Bullet engine frequency reported for safe-control-gym is typically much finer grained for improved fidelity. safe-control-gym quadrotor environment is not as light-weight as gym-pybullet-drones but provides the same order of magnitude speed-up and several more safety features/symbolic models.

Environment GUI Control Freq. PyBullet Freq. Constraints & Disturbances^ Speed-Up^^
Gym cartpole True 50Hz N/A No 1.16x
InvPenPyBulletEnv False 60Hz 60Hz No 158.29x
cartpole True 50Hz 50Hz No 0.85x
cartpole False 50Hz 1000Hz No 24.73x
cartpole False 50Hz 1000Hz Yes 22.39x
gym-pyb-drones True 48Hz 240Hz No 2.43x
gym-pyb-drones False 50Hz 1000Hz No 21.50x
quadrotor True 60Hz 240Hz No 0.74x
quadrotor False 50Hz 1000Hz No 9.28x
quadrotor False 50Hz 1000Hz Yes 7.62x

^ Whether the environment includes a default set of constraints and disturbances

^^ Speed-up = Elapsed Simulation Time / Elapsed Wall Clock Time; on a 2.30GHz Quad-Core i7-1068NG7 with 32GB 3733MHz LPDDR4X; no GPU

Run Tests and Linting

Tests can be run locally by executing:

python3 -m pytest ./tests/  # Run all tests

Linting can be run locally with:

pre-commit install  # Install the pre-commit hooks
pre-commit autoupdate  # Auto-update the version of the hooks
pre-commit run --all  # Run the hooks on all files

References

Related Open-source Projects


University of Toronto's Dynamic Systems Lab / Vector Institute for Artificial Intelligence