Sorry, but the problem is how to use a pen to draw machine readable shapes. Machines find reading QR codes and OP's triangles easier than reading letters.
Here's an example of some that were misclassified by an algorithm: http://www.concordia.ca/content/concordia/en/research/cenpar...
MICR E13-B: http://www.micr-fonts.com/MICRfont/micrfont.html
(*British. <grin>)
(Yes the phonetic alphabet is meant for ease of hearing by people, but writing a program to understand 26 distinct sounds can't be nearly as hard as natural language transcription.)