Sea Technology

JUL 2017

The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community

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32 st / July 2017 of Lexan for added strength and are also watertight so the sam- ples remain submerged while they are taken inside the vessel for processing. Each insert mea- sures 11.5 in. long, 8 in. wide and 6.5 in. deep. This allows sizable samples to be collected in each insert. The suction sampler consists of a 2-in. hose system and five discreet 2-liter buckets on a ro- tating carousel. A complete set of spare buckets allows for quick turnaround time between dives. The Tecnadyne Model 20 brush- less rotary actuator rotates the buckets on the carousel to an indexed inlet/discharge position for filling. A Tecnadyne Model 212 reversible, variable-speed suction pump is used to fill the buckets. The buckets come with a stainless steel mesh in the lid to prevent samples from exit- ing with the outflow from the pump. Different filter paper can be attached to the stainless steel mesh to further reduce particle size exiting with the outflow. The hose feeding the suction sampler is rigid and clear so objects stuck in the hose can be located. The inlet side of the hose terminates in a section of truncated Lexan tubing and is attached to a handle that can be grasped with the manipula- tor claw. A strong rubber-coated magnet was mounted over the top of the bio box to allow the suction hose to be "put up" when just the manipulator's claw function is required. The suction amount can be reduced for delicate objects or turned up full blast to vacuum sediments from the ocean floor. In ad- dition, the suction hose can be used to pick up objects that will not fit through the hose and place them in the bio box. The collection skid's subsea electronics bottle provides three RS232, two RS485 and one Ethernet connection, all with 24 VDC power available for adding more scientific equipment. Both the RS232 and RS485 connections are ac- cessed through DB9 female RS232 connections on the top- side control box. Communications for the skid are handled by a pair of 907+ Focal video/data multiplexer cards, one topside and one on the electronics bottle. HBOI added a serial expansion card on each multiplexer to accommodate the additional RS232 and RS485 communications and a 907 Diagnostic E card to the stack of cards for troubleshoot- ing purposes. The electronics bottle also provides two video channels and three channels that provide power and ground tion is not an issue. During the 2015 field season, the collection skid was used on four cruises for a total of 30.5 days. During these cruises, a total of 298 samples were collected. Comparably, if the ROV were using a single- function manipulator, this would have taken at least 298 dives, about 10 times as many as with the collection skid on the Mohawk ROV. As ship time increases in cost and funding resources remain tight in the scientific community, the science team must make every minute of bottom time count. The new sample collection skid capa- bility provides huge time and cost savings. Collection Skid Details, Components The sample collection skid is 16 in. high, 53 in. long, 32 in. wide, and weighs 300 lb. dry. The entire skid mounts under the Mohawk ROV with six indexed tabs that are bolt- ed to receivers on the bottom of the ROV and can be in- stalled or removed from the ROV in about 4 hr. This gives the science crew additional flexibility when planning di- verse long-term missions. All components on the skid are rated to at least 300 m. UVP staff chose the all- electric, five-function ECA Hytec Micro 5E manipulator for the ROV to preclude the weight and maintenance as- sociated with hydraulic units. This particular Micro 5E manipulator runs on 220 VAC pow- er and is oil filled for a depth rating of 300 m. It weighs a mere 6.06 lb. in the water; however, it can pick up 22 lb. in the air at full extension. A joystick box is used to control the manipulator functions. The opening and closing bio box is chain driven by a Tec- nadyne Model 20 brushless rotary actuator, slides in and out on two tracks, and has a sample capacity of 15 lb. in water weight. The lid remains stationary as the bio box slides out beneath it, revealing the segmented compartments. The bio box has two sets of removable box inserts with adjustable dividers to allow for a quick turnaround time between dives. The compartments are filled from back to front so that only empty compartments need be opened for sample place- ment, while compartments already containing samples re- main closed by the lid. The removable box inserts are made (Top and Bottom) Bio box open in preparation for removing samples post dive in the Gulf of Mexico May 2015. (Photo Credit: Brian Cousin, HBOI) A representation of sample types collected by UVP in 2015.

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