translation.en: It's trying to walk on the coarse terrain, sandy area, but depending on the moisture content or the grain size of the sand the foot's soil sinkage model changes.
translation.zh: 它试图在粗糙地形上行走， 沙地上， 取决于水分含量或沙粒大小的 脚下的泥土下沉模式变化。