What is the difference between a rigid body object and a dynamic object?

Question

What is the difference between a rigid body object and a dynamic object, aside from the fact that rigid body objects can rotate and move based on physical stimuli, and dynamic objects can move but always stay clamped to an upright position? Is there any other difference between the two?

Answer 1

It seems that your assumption is right Rigid Bodies add angular physics (angular velocity) to the behaviour of Dynamic objects.

Which makes a rigid body roll over when it collides with another object, while a dynamic object would just stop to move.

From Python Wiki: Physics Type

• NO_COLLISION No Collision, Disable collision for this object.
• STATIC Static, Stationary object.
• DYNAMIC Dynamic, Linear physics.
• RIGID_BODY Rigid Body, Linear and angular physics.
• SOFT_BODY Soft Body, Soft body.
• OCCLUDE Occlude, Occluder for optimizing scene rendering.
• SENSOR Sensor, Collision Sensor, detects static and dynamic objects but not the other collision sensor objects.
• NAVMESH Navigation Mesh, Navigation mesh.
• CHARACTER Character, Simple kinematic physics appropriate for game characters.

Answer 2

for reference. the dynamic type rigid body is subseptable to modifiers such as deform modifiers, smooth modifiers and things like shapekeys. With a dynamic type these can be animated on the fly and the physics shape is modified on a frame by frame basis...

the "deform" option is slightly different in that it only allows deformation on the initial frame of the calculation... so you can use both deform and dynamic in order to give, say , a complex skinned character mesh rigid body physics, which (unless the animated option is checked) will cause your character to fall to the ground.

for such complex rigid bodies (animated armature driven meshes) it is best to have the animated tickbox checked, as well as the dynamic tickbox, and the "deform" option also selected(and its tickbox checked) keep in mind deform is only available for mesh or convex type rigid bodies.

this setup will allow an animated character to remain animated whilst still influencing the rigid body objects around them... although the way the physics are calculated means the mesh has potentially infinite force on the rigid bodies, so fast movement of an animated passive rigid body is not recommended when in contact with a non animated active rigid body.