Grasping with PyBullet

This package provides an interface for grasp planning using PyBullet. It includes a grasp planner that can generate grasp candidates for a given object.

Installation

Pure Python

You can install the package using pip: python3 -m pip install pybullet_grasper
- when using python3.8 you might need to install upgrade pip and install development version of open3d
Or clone this repository git clone https://github.com/rustlluk/pybullet_grasper.git; go to src/pybullet_grasper and install it locally: python3 -m pip install -e .

ROS

You can install the package in ROS1 Noetic workspace
- Clone the repository or put the pybullet_grasper folder (inside src of this repo) to src of your ROS workspace
  - should be as catkin_ws/src/pybullet_grasper
    - this includes setup.py, src, objects, etc.
  - catkin_build it
See the branch ShapeGrasp repo for Dockerfile and Docker installation instructions

Usage

Pure Python

The easier option is to either:
- CLI in command line run python3 -m pybullet_grasper.grasper_main to see a demo of the grasp planner. This will print the results (if debug enabled) and/or save them to a file (if save_path provided)
  - possible command line options:
    - --object_name/-o: path to the .obj file
      - can be a relative path with respect to current folder, an absolute path, or a path related to installed path and be in pybullet_grasper/objects (when installed through pip it will be in sys.prefix/share/pybullet_grasper/objects)
    - --config_name/-c: path to .yaml config file
      - can be a relative path with respect to current folder, an absolute path, or a path related to installed path and be in pybullet_grasper/configs (when installed through pip it will be in sys.prefix/share/pybullet_grasper/config)
    - --ros/-r: whether to use ROS or not
      - if True, it will run the grasper as ROS node
      - requires roscore running and rospy installed
    - --service/-s: call the ROS service
      - requires node with rosservice running
      - here the object and config paths must be absolute, or the files must be located in ws/src/pybullet_grasper/configs and …./objects, respectively
    - --save_path/-sp: path where to save the generated grasps; str or None
      - will be saved as file with values seperated by “;”, so it is recommended to use .csv format
      - if None -> nothing will be saved
- API you can import the package main as from pybullet_grasper.grasper_main import main and call it result = main(object_name, config_name, ros=False, service=False), where:
  - object_name: path to the .obj file
    - can be a relative path with respect to current folder, an absolute path, or a path related to installed path and be in pybullet_grasper/objects (when installed through pip it will be in sys.prefix/share/pybullet_grasper/objects)
  - config_name: path to .yaml config file
    - can be a relative path with respect to current folder, an absolute path, or a path related to installed path and be in pybullet_grasper/configs (when installed through pip it will be in sys.prefix/share/pybullet_grasper/config)
  - ros: boolean, whether to run as a ROS node or not
  - service: boolean, whether to call as ROS service or not
  - save_path: str or None; path where to save the generated grasps
    - will be saved as file with values seperated by “;”, so it is recommended to use .csv format
    - if None -> nothing will be saved
  - result: pybullet_grasper.utils.GenerateGraspsResponse object
    - see utils.py for details on the response object and its attributes
  - see examples/example.py for usage
- Low-level API you can import directly from pybullet_grasper.grasp_generator import GraspGenerator
  - see grasper_main.py for usage

ROS

When you have ROS installed and the package installed, you can:
- ROS Node run the script as node (works the same as pure python basically, but uses ROS messages etc.)
  - use either the CLI or API options described above, but with --ros/-r (in CLI) or ros argument (API) set to True
    - see also grasper_main.py for low-level usage
  - roscore must be running for this
- ROS Service call the ROS service to get grasp candidates
  - to just test it, you can use the CLI (with --service/-s option) or API (with service=True argument) options described above
  - roscore and grasp_generator_service.py node must be running for this
    - you can run roslaunch pybullet_grasper main.launch to run the roscore and service
  - Otherwise, the service file is defined as:
    std_msgs/String object_name std_msgs/String[] grasp_type float32[] init_position --- geometry_msgs/Pose[] poses float32[] qualities float32[] poses_after_grasps
    and can be called as (see also example_service.py): ``` import rospy from pybullet_grasper.srv import GenerateGrasps, GenerateGraspsRequest

if __name__ == "__main__":
    # Here the path must be absolute or the .yaml must be in ws/src/pybullet_grasper/configs and .obj in ws/src/pybullet_grasper/objects
    config_name = "example.yaml"
    object_name = "example.obj"

    rospy.init_node("grasp_generator_node")

    rospy.set_param("config_name", config_name)

    rospy.wait_for_service("generate_grasps")
    generate_grasps = rospy.ServiceProxy("generate_grasps", GenerateGrasps)

    request = GenerateGraspsRequest()
    request.object_name.data = object_name
    request.init_position = [0, 0, 0]
    result = generate_grasps.call(request)
```
or from the command line as:
```
rosservice call /generate_grasps "{object_name: {data: 'example.obj'}, grasp_type: [{data: 'example.yaml'}], init_position: [0.0, 0.0, 0.0]}"
```

Config files

The pacakge uses .yaml config files to specify both parameters of the grasp planner and visualization/debug options. The default one can be found in src/pybullet_grasper/configs/default.yaml The main things to change are:

gripper: for now “robotiq” or “barrett”
- users can add new grippers adding the API in a similar form to the existing ones, available in bullet_classes.py
debug: boolean; when True additional prints are shown. Also neccessary when visualization.show_last enabled
visualization.show_last: boolean; when True, the best generated grasp candidate is visualized.
- Requires debug to be True as well.
visualization.debug_sleep: float; when show_last is enabled, it will most probably run super fast. debug_sleep can make the rendering slower (0.01) is a good value on most machines
analytical.enabled: boolean; when True, friction cones and GWS are computed (with epsilon-quality and GWS volume) and can be shown in the visualizer if show_last is enabled
- very preliminary version, will most like not work every time

Input Meshes and Processing

the input meshes must be in .obj format (Wavefront OBJ format). You can use third-party libraries like Meshlab, open3D, or Blender to convert your meshes to .obj format if they are in a different format.
We further employ the VHACD library to perform convex decomposition of the meshes. This steps takes some time in the beginning. But it is necessary for detection collision of object and gripper properly

License

` .. image:: https://img.shields.io/badge/License-CC%20BY%204.0-lightgrey.svg

target:

https://img.shields.io/badge/License-CC%20BY%204.0-lightgrey.svg

alt:

CC BY 4.0

<http://creativecommons.org/licenses/by/4.0/>`_

This work is licensed under a Creative Commons Attribution 4.0 International License.

` .. image:: https://i.creativecommons.org/l/by/4.0/88x31.png

target:

https://i.creativecommons.org/l/by/4.0/88x31.png

alt:

CC BY 4.0

<http://creativecommons.org/licenses/by/4.0/>`_

See licences of the used libraries like PyBullet, Open3D, etc. for more details.

Citing

When used, please cite this repository as follows:

@inproceedings{rustler2026ShapeGrasp,
      title={},
      author={},
      year={2026},
      booktitle={},
      organization={}}

Grasping with PyBullet

Installation

Pure Python

ROS

Usage

Pure Python

ROS

Config files

Input Meshes and Processing

License

Citing

pybullet_grasper