Constraint(bpy_struct)
base class — bpy_struct
subclasses —
KinematicConstraint, ObjectSolverConstraint, CameraSolverConstraint, ClampToConstraint, StretchToConstraint, PivotConstraint, PythonConstraint, LimitLocationConstraint, FloorConstraint, TransformConstraint, LimitScaleConstraint, LockedTrackConstraint, CopyScaleConstraint, RigidBodyJointConstraint, FollowPathConstraint, TrackToConstraint, LimitDistanceConstraint, MaintainVolumeConstraint, CopyRotationConstraint, FollowTrackConstraint, DampedTrackConstraint, CopyTransformsConstraint, LimitRotationConstraint, SplineIKConstraint, ChildOfConstraint, ActionConstraint, ShrinkwrapConstraint, CopyLocationConstraint

class bpy.types.Constraint(bpy_struct)
Constraint modifying the transformation of objects and bones

active
Constraint is the one being edited
Type:  boolean, default False 

error_location
Amount of residual error in Blender space unit for constraints that work on position
Type:  float in [inf, inf], default 0.0, (readonly) 

error_rotation
Amount of residual error in radians for constraints that work on orientation
Type:  float in [inf, inf], default 0.0, (readonly) 

influence
Amount of influence constraint will have on the final solution
Type:  float in [0, 1], default 0.0 

is_proxy_local
Constraint was added in this proxy instance (i.e. did not belong to source Armature)
Type:  boolean, default False 

is_valid
Constraint has valid settings and can be evaluated
Type:  boolean, default False, (readonly) 

mute
Enable/Disable Constraint
Type:  boolean, default False 

name
Constraint name
Type:  string, default “”, (never None) 

owner_space
Space that owner is evaluated in
 WORLD World Space, The constraint is applied relative to the world coordinate system.
 POSE Pose Space, The constraint is applied in Pose Space, the object transformation is ignored.
 LOCAL_WITH_PARENT Local With Parent, The constraint is applied relative to the local coordinate system of the object, with the parent transformation added.
 LOCAL Local Space, The constraint is applied relative to the local coordinate system of the object.
Type:  enum in [‘WORLD’, ‘POSE’, ‘LOCAL_WITH_PARENT’, ‘LOCAL’], default ‘WORLD’ 

show_expanded
Constraint’s panel is expanded in UI
Type:  boolean, default False 

target_space
Space that target is evaluated in
 WORLD World Space, The transformation of the target is evaluated relative to the world coordinate system.
 POSE Pose Space, The transformation of the target is only evaluated in the Pose Space, the target armature object transformation is ignored.
 LOCAL_WITH_PARENT Local With Parent, The transformation of the target bone is evaluated relative its local coordinate system, with the parent transformation added.
 LOCAL Local Space, The transformation of the target is evaluated relative to its local coordinate system.
Type:  enum in [‘WORLD’, ‘POSE’, ‘LOCAL_WITH_PARENT’, ‘LOCAL’], default ‘WORLD’ 

type
 CAMERA_SOLVER Camera Solver.
 FOLLOW_TRACK Follow Track.
 OBJECT_SOLVER Object Solver.
 COPY_LOCATION Copy Location, Copy the location of a target (with an optional offset), so that they move together.
 COPY_ROTATION Copy Rotation, Copy the rotation of a target (with an optional offset), so that they rotate together.
 COPY_SCALE Copy Scale, Copy the scale factors of a target (with an optional offset), so that they are scaled by the same amount.
 COPY_TRANSFORMS Copy Transforms, Copy all the transformations of a target, so that they move together.
 LIMIT_DISTANCE Limit Distance, Restrict movements to within a certain distance of a target (at the time of constraint evaluation only).
 LIMIT_LOCATION Limit Location, Restrict movement along each axis within given ranges.
 LIMIT_ROTATION Limit Rotation, Restrict rotation along each axis within given ranges.
 LIMIT_SCALE Limit Scale, Restrict scaling along each axis with given ranges.
 MAINTAIN_VOLUME Maintain Volume, Compensate for scaling one axis by applying suitable scaling to the other two axes.
 TRANSFORM Transformation, Use one transform property from target to control another (or same) property on owner.
 CLAMP_TO Clamp To, Restrict movements to lie along a curve by remapping location along curve’s longest axis.
 DAMPED_TRACK Damped Track, Point towards a target by performing the smallest rotation necessary.
 IK Inverse Kinematics, Control a chain of bones by specifying the endpoint target (Bones only).
 LOCKED_TRACK Locked Track, Rotate around the specified (‘locked’) axis to point towards a target.
 SPLINE_IK Spline IK, Align chain of bones along a curve (Bones only).
 STRETCH_TO Stretch To, Stretch along YAxis to point towards a target.
 TRACK_TO Track To, Legacy tracking constraint prone to twisting artifacts.
 ACTION Action, Use transform property of target to look up pose for owner from an Action.
 CHILD_OF Child Of, Make target the ‘detachable’ parent of owner.
 FLOOR Floor, Use position (and optionally rotation) of target to define a ‘wall’ or ‘floor’ that the owner can not cross.
 FOLLOW_PATH Follow Path, Use to animate an object/bone following a path.
 PIVOT Pivot, Change pivot point for transforms (buggy).
 RIGID_BODY_JOINT Rigid Body Joint, Use to define a Rigid Body Constraint (for Game Engine use only).
 SHRINKWRAP Shrinkwrap, Restrict movements to surface of target mesh.
Type:  enum in [‘CAMERA_SOLVER’, ‘FOLLOW_TRACK’, ‘OBJECT_SOLVER’, ‘COPY_LOCATION’, ‘COPY_ROTATION’, ‘COPY_SCALE’, ‘COPY_TRANSFORMS’, ‘LIMIT_DISTANCE’, ‘LIMIT_LOCATION’, ‘LIMIT_ROTATION’, ‘LIMIT_SCALE’, ‘MAINTAIN_VOLUME’, ‘TRANSFORM’, ‘CLAMP_TO’, ‘DAMPED_TRACK’, ‘IK’, ‘LOCKED_TRACK’, ‘SPLINE_IK’, ‘STRETCH_TO’, ‘TRACK_TO’, ‘ACTION’, ‘CHILD_OF’, ‘FLOOR’, ‘FOLLOW_PATH’, ‘PIVOT’, ‘RIGID_BODY_JOINT’, ‘SHRINKWRAP’], default ‘CAMERA_SOLVER’, (readonly) 
Inherited Properties
Inherited Functions
References