Abstract: A tether device includes a tether assembly disposed between two entities maintaining connection between the entities. A resilient element is integrated with the tether assembly. A geometry of the tether assembly and the resilient element create first and second resilient element and tether force-displacement responses when the resilient element and tether assembly are together subjected to at least first and second axial displacement forces. The second axial displacement force is greater than the first axial displacement force. The first force-displacement response, when subjected to the first axial displacement force, is greater than the second force-displacement response when subjected to the second axial displacement force. The geometry can include a tether configured in a serpentine formation in a relaxed position. The serpentine formation straightens taut when the tether is fully extended by the second axial displacement force. The geometry can also include multiple O-rings.

Abstract: A tether device includes a tether assembly disposed between two entities maintaining connection between the entities. A resilient element is integrated with the tether assembly. A geometry of the tether assembly and the resilient element create first and second resilient element and tether force-displacement responses when the resilient element and tether assembly are together subjected to at least first and second axial displacement forces. The second axial displacement force is greater than the first axial displacement force. The first force-displacement response, when subjected to the first axial displacement force, is greater than the second force-displacement response when subjected to the second axial displacement force. The geometry can include a tether configured in a serpentine formation in a relaxed position. The serpentine formation straightens taut when the tether is fully extended by the second axial displacement force. The geometry can also include multiple O-rings.