Center of Mass
The center of mass (in zero-g) or short CoM, also known as center of gravity (in gravity), is the middle of a grid, calculated by the physics engine.
The center of thrust and center of lift are not considered in Space Engineers, compared to games like Kerbal Space Program.
Where is the center of mass?
Use the Info Screen to make the center of mass (and Grid Pivot) visible.
The center of mass is recalculated whenever the grid mass changes. This can happen by adding or removing blocks and also by adding or removing items inside block's inventories (like Cargo Containers).
Center of mass does not have to be where a block exists. A few ship shapes can make it very easy to have the CoM in an empty area, like a hollow cube, a horseshoe, a donut, etc.
Why do I care about the center of mass?
In contrast to real-life physics, Space Engineers always applies thrust and rotation to the center of mass, even if the thrusters or gyroscopes are placed asymmetrically; this simplification prevents tailspinning.
- Knowing where the CoM is on a ship or rover is advantageous when placing gyroscopes close to the center for best rotation efficiency[1]
- Placing Parachutes Hatches symmetrically around the CoM stabilises the landing and prevents tilting.
- Any mobile grid (like a rover, walker, or a tall rocket) in gravity will tip over when the CoM is unsupported. Keep the CoM low and centered!
Counterintuitively, Space Engineers does not realistically calculate tensile strength, so a static grid such as a bridge won't collapse, even if the CoM is massively under-supported.