Help Adding pin constraints to a rope at runtime

[Gieve]

What line is the exception pointing to in your code?

Code:

NullReferenceException: Object reference not set to an instance of an object
Obi.RopeMaker.AddPendulum (Obi.ObiCollider pendulum, Vector3 offSet)
(at Assets/Scripts/RopeMaker.cs:65)
RopeSetup.MakeRopes () (at Assets/Scripts/RopeSetup.cs:58)
RopeMakerEditor.OnInspectorGUI () (at Assets/Editor/RopeMakerEditor.cs:14)
UnityEditor.InspectorWindow.DrawEditor (UnityEditor.Editor[] editors, Int32 editorIndex,
Boolean rebuildOptimizedGUIBlock, System.Boolean& showImportedObjectBarNext,
UnityEngine.Rect& importedObjectBarRect)
(at C:/buildslave/unity/build/Editor/Mono/Inspector/InspectorWindow.cs:1253)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

The Full Error read out, 

points at line 65 the AddConstraint function call, and then refers back to all referencing code.