Physics

The Physics component enables real-world behavior in your scenes, such as gravity, collisions, and physical interaction between objects. Use it whenever you want a dynamic simulation (objects falling, bumping, sliding, being pushed, etc.).

Properties

Body Type

The Body Type defines how the object will behave in the simulation, in other words, how the physics engine treats the object during simulation. There are two types of behaviour: dynamic and kinematic.

• Dynamic: a dynamic body is fully controlled by the physics engine, and is affected by gravity, collisions, and moves only based on physical forces and contacts.

• Kinematic: A kinematic body is moved by you, by scripting for example, and is not affected by physics forces. However, it can still collide with other bodies, especially dynamic bodies.

• Static: A static body does not move and behaves as if it has infinite mass. It is not affected by forces or collisions, but other objects can collide with it.

Collider

A Collider defines the collision shape used for contacts and intersections used by the physics engine. Colliders don’t need to match the visual mesh perfectly, simpler shapes will have a better and more stable performance.

• Box: A box-shaped collider around the object.
• Sphere: A spherical-shaped collider.
• Capsule: A capsule-shaped collider (cylinder with rounded ends).
• Cylinder: a cylindrical-shaped collider.
• Convex Hull: creates a convex collision mesh that wraps around the object’s visual mesh.

Notes and best practices

• For heavy simulations try to choose the simplest collider that gives you good results (Box/Sphere/Capsule are typically the most stable).
• If an object should move naturally, set it to Dynamic.
• If an object is moved by a controller (robot axis, conveyor-driven parts), use Kinematic.