ABSTRACT
A catastrophe machine is a small toy made out of elastic bands designed to illustrate catastrophe theory, and in particular the cusp (or Riemann-Hugoniot) catastrophe. The machine obeys the fundamental requirement of catastrophe theory. The author designed the machine for pedagogical reasons, in order to provide a concrete example in which all the variables were obvious and measurable, and the relationship between them differentiate and computable. Then he found it so illuminating to experiment with, giving such a powerful intuition of how a continuous change of control can cause discontinuous jumps in behaviour. This jump is called a catastrophe. If the disk were in the minimum that was annihilated, then it will have to jump into the other minimum. Any application of catastrophe theory satisfying a differential equation with this property will exhibit delay—for example the applications to heartbeat and nerve impulse.
