重力感应，三个方向，x，y，z 不同方向不同值-Gravity sensing, three directions, x, y, z different values ​ ​ in different directions

船舶水动力模型，MMG模型，可用于船舶操纵性仿真，自航模试验如回转试验、Z型试验等-Ship hydrodynamic model, MMG model, can be used for ship maneuverability simulation, self model test, such as rotation test, Z test, etc.