Yuval Tassa
a264d0bc8b
https://youtu.be/GioWwB36XHI The new geom attribute adhesion (units of force, signed; pair-level override) translates the contact friction cone along its normal so that the force origin lies strictly inside it. Consequences: each contact can pull with up to the given force before breaking, and the tangential friction budget becomes mu*(f_N + adhesion) -- the Mohr-Coulomb yield condition with cohesion c = mu*adhesion -- so lightly-squeezed grasps retain a guaranteed friction floor. A translated cone factors exactly into {constant attractive force} + {original cone}, so no solver kernels change. The implementation is this factorization: a constant attraction along contact normals accumulated into the new mjData.qfrc_adhesion (summed into qfrc_passive), plus a bias of adhesive contact rows' reference acceleration (aref += R*adhesion), which makes resting penetration exactly independent of adhesion. Contacts of adhesive pairs remain active throughout the gap zone, producing rows with positive violation whose reference acceleration pulls: a tether that resists pull-off smoothly, captures objects released within the band into steady contact, and detaches at the specified force. Adhesion values of the two geoms combine by sum; explicit pairs override. mj_contactForce reports the net interface force (cone force minus the adhesive pull), whose normal component can now be negative. Negative adhesion is allowed and produces a repulsive offset (air hockey). PiperOrigin-RevId: 950858148 Change-Id: I879c08eba7ae501e5c0f8c2f807167344da4c2bc
MuJoCo Python Bindings
This package is the canonical Python bindings for the MuJoCo physics engine. These bindings are developed and maintained by Google DeepMind, and is kept up-to-date with the latest developments in MuJoCo itself.
The mujoco package provides direct access to raw MuJoCo C API functions,
structs, constants, and enumerations. Structs are provided as Python classes,
with Pythonic initialization and deletion semantics.
It is not the aim of this package to provide fully fledged
scene/environment/game authoring API, as there are already a number of existing
packages that do this well. However, this package does provide a number of
lower-level components outside of MuJoCo itself that are likely to be useful to
most users who access MuJoCo through Python. For example, the egl, glfw, and
osmesa subpackages contain utilities for setting up OpenGL rendering contexts.
Installation
The recommended way to install this package is via PyPI:
pip install mujoco
A copy of the MuJoCo library is provided as part of the package and does not need to be downloaded or installed separately.
Source
IMPORTANT: Building from source is only necessary if you are modifying the Python bindings (or are trying to run on exceptionally old Linux systems). If that's not the case, then we recommend installing the prebuilt binaries from PyPI.
If you need to build the Python bindings from source, please consult the documentation.
Usage
Once installed, the package can be imported via import mujoco. Please consult
our documentation for
further detail on the package's API.
We recommend going through the tutorial notebook which covers the basics of
MuJoCo using Python:
Versioning
The major.minor.micro portion of the version number matches the version of
MuJoCo that the bindings provide. Optionally, if we release updates to the
Python bindings themselves that target the same version of MuJoCo, a .postN
suffix is added, for example 2.1.2.post2 represents the second update to the
bindings for MuJoCo 2.1.2.
License and Disclaimer
Copyright 2022 DeepMind Technologies Limited
MuJoCo and its Python bindings are licensed under the Apache License, Version 2.0. You may obtain a copy of the License at https://www.apache.org/licenses/LICENSE-2.0.
This is not an officially supported Google product.