Introduction

Abstract

We watch a mobile robot making his way to clean the floor in a furnished room. He starts moving in an outward spiral. Then, he bumps into the wall or a piece of furniture, and he bounces back in a random direction. After a while, he has covered all of the areas that he can reach. He is blind, without a camera. However, he can touch a surface to feel whether it is a wall or the stairs. When he feels hungry, he moves over to the power charger for a boost of energy. So as not to anthropomorphize his purposes, I used a long-exposure filming app on my phone to trace his path in a single image. The path is a laborious sequence of irregular, angular segments – not quite a random walk, nor optimal movement but complex and hard to describe. Everything seems spontaneous, but it works out eventually and the floor is cleaned. I then compare the traced path of this cleaning robot to that of a foraging ant, a stream of Internet packets, and even a malicious computer virus. I found that all of their paths are surprisingly similar: they have a general sense of purpose, but they cannot foresee all of the obstacles in between. Therefore, they must adapt their course repeatedly with allowable changes in direction and take detours around any barrier.