Monday, December 29, 2014

A Cellular Automaton (Ant) that Counts in Binary

   In the previous post I described the update to my original Langton's Ant project.
   In this post I describe a new Scratch project that is a variation of Langton's Ant.
   A small change in the rules governing Langton's Ant creates an ant that counts in binary!
   The Binary Ant builds a vertical pattern that theoretically, goes on forever.
   For an introduction to the Binary Ant, click on this video.
   I have written a detailed description of the pattern created by the ant and the Scratch code used to model the ant. If you would like a free PDF copy, send your request to

Updates to My Langton's Ant in Scratch Project

   This is an update to my original Langton's Ant project. This update now allows you to experiment with Langton's Ant by placing the ant in a circle, square, triangle, or near a line segment.
You can view and/or download this project by clicking on this link.
   As you can see in this screen shot, a circle, triangle, square, and line segment are on the home screen. Click on the green flag and then click on one of the shapes and drag it so that it traps the center of the ant (the small red circle). Or, click on and drag the line segment near to the red dot. Then click on the head of the ant. You will see the ant shrink to size of the grid it will be moving on and then start moving. 
   How the ant will interact with figures in the plane is any ones guess because there is no way to predict the pattern the ant will create when it interacts with another figure. Changing the Direction the ant starts in is another variable.
   Over the years I have collected several interesting and surprising figures created when the ant interacted with one or more figures.
   For a fascinating discussion about Langton's Ant download and read the following article.

Monday, December 1, 2014


   In biology, a taxis is the response of an organism to an environmental stimulus.           
   Galvanotaxis (or electrotaxis) is the movement of an organism in response to an electric field. 
   If platinum electrodes are inserted into a chamber filled with water containing a culture of paramecium, when an electric current is introduced into the chamber, the paramecia move towards the negative electrode.

   I simulated galvanotaxis in Scratch. Click on the play button to watch a video of the Scratch project in action.

   You can view and download the project by clicking on this link.
   A description of the code and how it works is available on request by sending an email to: