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script/controller.py

@@ -1,5 +1,5 @@
 #! /usr/bin/env python
-"""Module for executing control for a given effector"""
+"""Library for executing control for a given effector"""
 
 from __future__ import division
 import os
@@ -29,6 +29,7 @@ NAO_ARM = 0.22
 
 
 def xyz(joint):
+    """Get 3D coordinate of a joint in torso frame."""
     return np.array(mp.getPosition(joint, FRAME_TORSO, False),
                     dtype=np.float64)[:3]
 
@@ -88,6 +89,7 @@ def jacobian(side):
 
     ax_order = (y_axis, z_axis, x_axis, z_axis)
 
+    # Calculate the Jacobian after the formula from the report
     axes = np.concatenate(
         [get_transform(side + j).dot(ax) for j, ax in zip(JOINTS, ax_order)],
         axis=1