When you play with your toys outside, sometimes you like to push them really hard or drop them from high up. This can make them go up and down and shake around a lot. When big machines and buildings go through different physical stresses and strains, they also go up and down and shake around a lot. This is called mechanical fatigue. But unlike your toys, machines and buildings can get really hurt if they experience too much mechanical fatigue.
To help make sure machines and buildings stay safe, engineers use something called the rainflow-counting algorithm. This special math tool helps them keep track of all the up and down movements, or "cycles," that happen over time. It's like counting the times you go up and down on a swing at the park. By knowing how often cycles happen and how much they shake things around, engineers can tell when a machine or building might be getting too much mechanical fatigue. This helps them fix the problem before it gets too serious and causes damage or accidents.
So, the rainflow-counting algorithm is like a special tool that helps engineers keep track of how things move up and down, so they can make sure everything stays safe and nothing breaks.