Interactive Signal Machine

A signal machine is a 1-dimensional dynamical system consisting of particles moving through time along with a set of interactions. When particles collide, they are replaced by new particles according to a ruleset, given as a map of sets of particle types to new types. When considered as a computational model, it is known to be Turing complete.

In the generated diagram, particles are traced downward as time progresses. Number values can be entered as integers or fractions (e.g. 1/2).

Particle types

Each particle travels at a constant velocity determined by its type. Here you can define types on each line with an arbitrary name, velocity, and HTML color.

name velocity color


When two or more particles collide, they are replaced according to a ruleset. If a rule is not defined below for a particular collision, no interaction will take place.

inputs outputs

Initial positions

type position

Collision limit


Pixels per position coordinate