Introduction

The physics constraints available in the non-game modes are meant to be attached to an object.The constraint then has fields which can be pointed at the two physics-enabled objectwhich will be bound by the constraint.The Empty object provides a location and axis for the constraint distinct from the two constrained objects.The location of the entity hosting the physics constraint marks a location andset of axes on each of the two constrained objects.These two anchor points are calculated at the beginning of the animation and their position andorientation remain fixed in the local coordinate system of the object for the duration of the animation.The objects can move far from the constraint object, but the constraint anchor moves with the object.If this feature seems limiting, consider using multiple objects with a non-physics Child of constraint andanimate the relative location of the child.

Also you can create Rigid Body Constraint on of the two constrained objects withRigid Body Constraint button of the Physics tab in the Properties editor.This constraint is dependent on the object location and rotation on which it was created.This way, there are no Empty object created for the constraint.The role of the Empty object is put on this object.The constrained object can be then set as Passive type for better driving the constrain.

Rigid Body Constraint panel.

• Enabled
• Specifies whether the constraint is active during the simulation.
• Disable Collisions
• Object 1
• First object to be constrained.
• Object 2
• Second object to be constrained.
• Breakable
• • Impulse strength that needs to be reached before constraint breaks.
• Override Iterations

• Allows to make constraints stronger (more iterations) or weaker (less iterations)than specified in the rigid body world.

  • Iterations
  • Number of constraint solver iterations made per simulation step for this constraint.
• Limits