Saipem is taking the lead in advancing the capabilities of FlatFish, an autonomous underwater vehicle (AUV), being developed by Shell for commercial application by 2020. The AUV will be able to perform complex inspections of risers, data harvesting from subsea sensors, contactless monitoring of the cathodic protection systems, and will operate from a “flying-hanging garage” for the launching/recovering and subsea recharging/reprogramming of the AUV from offshore platforms.
Previous development was done by SENAI CIMATEC School of Technology in Brazil in partnership with the German Research Center for Artificial Intelligence (DFKI) over 4 years, funded by Brazil’s ANP R&D program and the Brazilian Agency for Industrial Research and Innovation (EMBRAPII).
SENAI CIMATEC and Saipem do Brasil entered into a contract with Shell Brasil on 3 December 2018 for continued development to bring the FlatFish to commercialization.
The FlatFish AUV inspects a subsea isolation valve (SSIV). Video source: DFKI.
The Making of FlatFish
The AUV is compact, designed to acquire a high-resolution, textured 3D model of an underwater structure within an oil and gas asset using a variety of acoustic and optical sensors and a subsea docking station. DFKI describes it as “agile” and capable of hovering during inspection and is designed to stay submerged for extended periods of time.
DFKI provided the mechanical and electrical design of the vehicle as well as manufacturing and integration of the AUVs. The basic software modules were implemented at DFKI to allow for sensor data processing and vehicle control and navigation solutions such as waypoint following. A waypoint is the set of coordinates representing the longitude and latitude of a given position
For the evaluation of energy and high-bandwidth data transfer while submerged, the docking station demonstrator was equipped with optical data transmitters and electrical contacts for battery charging. The data transfer system is based on blue LEDs and achieved data rates of 2.8 MBit/s during the final tests witnessed by representatives from Shell (Rio, Brazil, and Houston) and from SENAI-CIMATEC (Salvador, Brazil).
The energy transfer is based on electrical contacts made of titanium, which are isolated from the surrounding salt water by a sealing system. During the testing, successful underwater battery charging was shown several times.
The vehicle will be docked near an offshore facility and connected to a power supply and data uplink. The operator (either on the facility or at a remote location) commands the vehicle to perform an inspection task. Where the inspection target is remote from the facility the AUV undocks and follows a pipeline or flowline to a target area while collecting acoustic and visual data of the pipeline or flowline.
When the target area is reached, acoustic and visual data from the inspection object is gathered. The vehicle then backtracks using acoustic and visual homing algorithms to return and connect to the docking station. The recorded data is then uploaded to be processed by automated systems and/or the human operator while the AUV’s battery is being recharged. At the same time, the operator has the option of defining a follow-up mission.
Shell, as the industry partner, is taking the results from the FlatFish project (docking, autonomous inspection, 3D reconstruction, opto-acoustic homing, underwater data and energy transfer) to continue development.
