ClosedLoopMotion

Examples of motion of robot with closed kinematic loops. This repo illustrates methods proposed in ICRA 2025 submission

How to cite

@unpublished{dematteis:hal-04716938,
  TITLE = {{Optimal Control of Walkers with Parallel Actuation}},
  AUTHOR = {de Matte{\"i}s, Ludovic and Batto, Virgile and Carpentier, Justin and Mansard, Nicolas},
  URL = {https://hal.science/hal-04716938},
  NOTE = {working paper or preprint},
  YEAR = {2024},
  MONTH = Oct,
  PDF = {https://hal.science/hal-04716938v1/file/ICRA_2025___Optimal_Control_of_Closed_Loop_walkers-submission.pdf},
  HAL_ID = {hal-04716938},
  HAL_VERSION = {v1},
}

Installation

Using docker

• Pull the docker image

docker pull ghcr.io/ludovicdematteis/closedloopmotion:latest

• Run the docker image

docker run --rm --network host -it ghcr.io/ludovicdematteis/closedloopmotion:latest

• Inside the docker

git clone https://github.com/LudovicDeMatteis/ClosedLoopMotion
cd ClosedLoopMotion/

Nix

Using nix you can either

• Start the nix environnement from this repo

git clone https://github.com/LudovicDeMatteis/ClosedLoopMotion
cd ClosedLoopMotion 
nix develop

• or build the docker file

git clone https://github.com/LudovicDeMatteis/ClosedLoopMotion
cd ClosedLoopMotion 
nix build -L .#docker
docker load < result
docker run --rm --network host -it ghcr.io/ludovicdematteis/closedloopmotion:latest

From source

To use this project, following dependencies are required:

• Crocoddyl fork on branch topic/contact-6D-closed-loop
• sobec on branch icra_2025
• toolbox-parallel-robots
• example-parallel-robots

Usage

Run either

python main.py

or

python main_nogui.py

You can then choose the desired motion, the robot and set parameters. Once the solver ends, you can replay the final trajectory or show plots of the results. Make sure to open the Meshcat visualizer at http://127.0.0.1:7000/static/

Table of contents

• loaders - The repo contains utility loaders based on example-parallel-robots, included in the loaders folder. Current version supports Battobot and Digit. The models of Disney robot and Kangaroo are to be fixed and added (cf Future Improvements)
• params - Params for different motions on included in folder params.
• tests - This folder contains tests on crocoddyl functions, this should be complete.
• motions - These scripts are examples of motions on different robots, named {motion}_{robot}_{open/closed}.py
• main.py creates a GUI using tkinter and asks for a desired motion, desired robot and parameters options.
• main_nogui.py does the same as main.py with a text interface (to allow use in docker)

Future Improvements

We list in arbitrary order the expected improvements

• Adding new robot models (Disney robot, Kangaroo...)
• Adding new motions (half-turn, flip, running...)
• Add tests for crocoddyl functions