pylgmath

pylgmath is a Python library for handling geometry in state estimation problems in robotics. It is used to store, manipulate, and apply three-dimensional rotations and transformations and their associated uncertainties.

There are no minimal, constraint-free, singularity-free representations for these quantities, so lgmath exploits two different representations for the nominal and noisy parts of the uncertain random variable.

• Nominal rotations and transformations are represented using their composable, singularity-free matrix Lie groups, SO(3) and SE(3).
• Their uncertainties are represented as multiplicative perturbations on the minimal, constraint-free vectorspaces of their Lie algebras, *so**(3)* and *se**(3)*.

This library uses concepts and mathematics described in Timothy D. Barfoot's book State Estimation for Robotics. It is used for robotics research at the Autonomous Space Robotics Lab; most notably in the STEAM Engine, a library for Simultaneous Trajectory Estimation and Mapping.

Installation

## PyPI
pip install asrl-pylgmath

## Source
git clone https://github.com/utiasASRL/pylgmath.git
pip install -e pylgmath  # may need to replace `pip` with `pip3` if not using a virtual environment.

Unit tests

Use pytest to run the unit tests:

pytest ./tests

License