I spent a month in factories in China on a research grant called Hacking Manufacturing from MIT Media Lab. You can read about my experience here: https://www.media.mit.edu/posts/hacking-manufacturing-research-on-the-factory-floor/
In August 2017, a group of Media Lab students went to Shenzhen, where they spend a month there in two factories. This is a documentary about what they experienced, made and learned.