Patent ID: 8191636

Claim:
A motion compensation apparatus for conducting intervention operations on a subsea installation from a floating vessel comprising: a. a first support frame having an opening; b. a second support frame disposed within said opening of said first frame; c. at least one lifting cylinder having a first end and a second end, wherein the first end of said at least one cylinder is connected to said first support frame, said second end of said lifting cylinder is connected to said second support frame; and d. a monitoring control assembly comprising: i. at least one electronic sensor adapted to measure support frame tension, speed or position data; and ii. at least one processor; wherein said at least one processor controls said at least one lifting cylinder based on data measured by said at least one electronic sensor and adjusts the vertical position of said second support frame relative to said first support frame to maintain a substantially constant vertical distance between said second support frame and said subsea installation.