Here is the first pop-up book I ever made:
There are total of 11 pages, I integrated some basic paper actions and used them in this book. As I am making this book, I understand the paper movement more clearly.
If we look at it mathematically, every paper movement follows some laws. For example, each movement involves changing the angle in three dimensions. The most common change is that the angle between the two faces increases, so that the part that pops up can be supported when the page is opened, which means that the support structure will be somehow symmetrical. If we can summarize such paper movements with mathematical models, we may be able to draw more possibilities through such these models in the future.
Ruhan Yang 