There is no such thing as a perpetual motion machine. Every scientist and engineer knows that because you cannot create energy from nothing. Friction will slowly "destroy" the energy in the machine and cause the machine to stop eventually.

But in the financial sense, you could build a "perpetual" income machine. This is our model:

At 60, we have built up a networth of $6m

Taking away our primary home value ($1.5m) we have $4.5m to invest

But as we are already retired, we took out $1m to fund our expenses at $100k pa. This leaves $3.5m for investment.

Our $3.5m is currently placed in conservative investment instruments giving us only 3% return or about $100k pa.

After 10 years, at 70, we would have used up the $1m we put aside for expenses. But by then, our passive income would have generated another $1m for us.

Unfortunately the inflation (just like friction) will slowly eat away the value of the new $1m. It will not buy us as much as the current $1m. So unless our investment returns can beat inflation, we would not be able to have a perpetual income machine.