polytope_roll

Robotic manipulation to roll a polytope using trajectory optimization and controls.

Installation instructions

We recommend making a python virtual environment. Once navigating into a desired directory, clone the repository and set up the virtual environment via:

git clone https://github.com/ebianchi/polytope_roll.git
cd polytope_roll
python3 -m venv venv
venv/bin/pip install --upgrade pip
source venv/bin/activate

At this point, ensure that /desired/location/polytope_roll is included in the $PYTHONPATH environment variable. Without changing directory, you can do this immediately after the previous step via:

export PYTHONPATH=$PYTHONPATH:$PWD

Then requirements can be installed via three steps. First, pip install the requirements in the current directory via:

pip install .

This installs all of the bundled requirements, including, at the time of creation of this repository, imageio, matplotlib, numpy, and sympy. However this also installs polytope_roll as a package, which will be problematic if you want to edit the source code in this repository. You can remove the polytope_roll package while keeping its requirements via:

pip uninstall polytope_roll

Lastly, there is one remaining requirement that, in our experience, has only worked properly if directly pip installing the git repository url.

pip install git+https://github.com/AndyLamperski/lemkelcp.git

This installs AndyLamperski's python implementation of the Lemke algorithm for solving linear complementarity problems (LCPs), which is used to run the 2-dimensional toy simulation via Stewart and Trinkle, 1996.

Run example

You can run an example of a 2-dimensional polytope falling under gravity and colliding inelastically with the ground via:

python toy_2d/src/simulate_polytope.py

This call should generate a gif of the falling polytope, saving it into polytope_roll/toy_2d/out/.

Debugging

In case the example does not run, try ensuring the installed packages match the following versions:

$ pip list
Package         Version
--------------- -------
contourpy       1.0.5
cycler          0.11.0
fonttools       4.38.0
imageio         2.22.2
kiwisolver      1.4.4
lemkelcp        0.1
matplotlib      3.6.1
mpmath          1.2.1
numpy           1.23.4
packaging       21.3
Pillow          9.2.0
pip             22.3
pyparsing       3.0.9
python-dateutil 2.8.2
setuptools      65.4.1
six             1.16.0
sympy           1.11.1