translation.en: Now, David builds mathematical models of this and then he tests those in the lab, but before he does that, he works with dancers to figure out what kinds of models to build in the first place.
translation.zh: 大卫先创建数学模型，然后再到实验室测试， 但是在这之前，他和舞蹈演员一起 研究首先需要创建哪种模型。