Patent ID: 7328741

Claim:
In an offshore drilling and/or production system having a riser extending between subsea well equipment and a floating vessel, a riser monitoring assembly comprising: a lower riser measurement instrument module connected to a lower portion of the riser to provide real-time dynamic orientation data for the lower portion of the riser; an upper riser measurement instrument module connected to an upper portion of the riser to provide real-time dynamic orientation data for the upper portion of the riser; a computer carried by the vessel and having a memory containing a table of models of the structure of the riser under various orientations along its length and riser system analyzing software stored in the memory, the riser system analyzing software responsive to the dynamic orientation data from the riser measurement instrument modules and the models in the memory to analyze and determine the dynamic structure of the entire riser; a first data communication line connected between the lower riser measurement instrument module and the vessel to provide communications between the lower riser measurement instrument module and the vessel; and a second data communication line connected between the upper riser measurement instrument module and the vessel separate from the first data communication line to provide communications between the upper riser measurement instrument module and the vessel.