How to visualise servo behaviour
==================================

.. _visualise-servo-behaviour:

Visualise the relationship between pulse-widths and angles
----------------------------------------------------------

A Jupyter Notebook is included, to  help visualise the relationship between pulse-widths and angles, using the same ``numpy.polyfit()`` as used in the BrachioGraph:

.. image:: /images/pw-angles.png
   :alt: 'Pulse-widths to angles'
   :class: 'main-visual'

To run the Notebook, you'll first need to install Jupyter Lab (it's not included in the
provided ``requirements.txt``) with::

    pip install jupyterlab

Then launch it with::

    jupyter lab pulse_widths.ipynb

The values used in the Notebook are exactly as provided for ``servo_1_angle_pws`` and ``servo_2_angle_pws`` in an
actual BrachioGraph definition, for example::

    servo_angle_pws = [
        [-162, 2490],
        [-144, 2270],
        [-126, 2070],
        [-108, 1880],
        [ -90, 1680],
        [ -72, 1540],
        [ -54, 1360],
        [ -36, 1190],
        [ -18, 1020],
        [   0,  830],
        [  18,  610],
    ]