Large Vessel Lift On/Lift Off Crane Transcript

Video provided courtesy of Pentagon Channel News

Speaker Key:

• Narrators: Sgt. Ted McDonald and Sgt. Jeremy Ross, Pentagon Channel News
• May: Ed May, program manager, Oceaneering International
• Hess: Dr.  Paul Hess, program officer, ONR Ship Systems and Engineering Program

Narrator: Hello and welcome. I’m Sgt. Ted McDonald. One of the things peculiar to living on the ship is that you can’t just run out to the drug store or grocery store to pick up more of whatever you need. When food, fuel, and even ammunition run low, it needs to be replenished, sometimes at sea. Sgt. Jeremy Ross tells us about an innovative way of getting ship supplies to hold steady during a sometimes rocky delivery.

Narrator: Getting supplies aboard ships can be a perilous mission especially when the task must be performed at sea – even worse when the cargo is a 20,000-pound container.

May: The problem that we’re faced with is we have to pick something off a second ship that moored along your second ship, and both ships are rocking and rolling in the seaway.

Ross: It doesn’t always make for a soft landing, so the people at the Office of Naval Research, along with Oceaneering International, figured if they can’t beat the waves, they should join them.

May: This crane will actually follow the motions of the ship.

Ross: Watch the orange lift which, in this demonstration, is mimicking the motion of a ship. As it goes up, the crane lifts the container up. Each movement, heavy surge, sway, roll, pitch or yall, is monitored by sensors and cameras and shadowed by the crane.

Hess: Both visual as well as the response of the accelerations of the crane, the strain, the degree to which the structure is deforming, if you will, all lead to how control algorithms cause the crane to respond so that any ship in the crane’s geometry is accounted for.

Ross: This is a drawing of the entire crane. What you saw outside is this part. And this is a 1:20 scale model of the crane working with a would-be container ship at sea. Without the work of cameras and sensors, it’s difficult to center the crane over the container, but once the system is activated, the task becomes much easier.