A dynamic stabilization device, system, and method for use with a spinal motion segment includes a first bone anchor assembly, a second bone anchor assembly, a first articulation element and a second articulation element. The contact includes a main body; a movable portion held by the main body so as to be reciprocal in directions of increasing and decreasing of a projecting amount thereof outwardly of the main body; and a biasing mechanism that biases the movable portion in such a direction that the projecting amount of the movable portion increases. The coupling section has an opening and a directing section formed on the periphery of the opening with an inner diameter greater than the coupling section, and a chamfered edge located between the directing section and the coupling section to facilitate insertion and assembly of the second elastic element in the coupling section. In this way, a determination of print quality may be determined irrespective of the influence of the inherent qualities or pre-existing print markings. The target interface system likewise detects when a selected system component is absent, unpowered, andor wrongly powered and provides contention detection.