Length (m), overall: 18.3
Hull length (m): 16.2
Beam (m), overall: 8.2
Draft (m): 0.8
Lightship (tonnes): 30
Hull material: Aluminum
Speed (kts): 29 (90% MCR)
Engines (hp): 2 x 515
Passengers + Crew: 12 + 3
Cargo (tonnes): 4
By Tea Tramontana
On the Southwestern tip of Australia, in the town of Dunsborough and facing the Indian Ocean’s Geographe Bay, a handful of engineers are drawing up the final design for the Nauti-Craft catamaran, applying rally car suspension system experience to offshore watercraft.
With support from the Carbon Trust, the Nauti-Craft team has designed and built a 1:10 scale catamaran prototype that was tested in a local lake. The Australian team has already proved the concept on an 8 meter quadmaran prototype:
“We proved that we can transport turbine technicians comfortably to the wind farm and conduct a safe transfer from the vessel to the turbine in a 2 to 3 meter significant wave height”, says Chris Heyring.
The Nauti-Craft system decouples roll, pitch, warp, and heave inputs to maintain a level attitude. On the basis of the test results, the Nauti-Craft team now has two models on the drawing table – one of them an 18 meter vessel designed for the offshore wind turbine industry:
“In next few months, we will have finalized the preliminary design of the vessel, with detailed specifications and cost”, says Chris Heyring, who invented back in 1980 the automotive suspension technology that is now used by a range of car producers. Now he and his team want to conquer the offshore sector, inviting industry partners and government financing to participate in the building of a fullscale prototype:
“We are planning to start building both catamaran and quadmaran demonstration vessels in the next few months to show to different potential partners how the system works in reality and the prospect of experiencing the system as a passenger”.
A passive-reactive suspension system isolates the motions of the sea from the deck of the vessel, ensuring safe and stable transport of personnel and transfer to offshore turbines.
The Nauti-Craft concept isolates the vessel deck from the hulls using a sophisticated hydraulically interconnected suspension system. The shape and design of the hulls provide the first response to the waves while the suspension system provides the second. This works both at high speeds and when stationary. This ride control system with an automotive heritage works like a ‘hydraulic computer’ that automatically allows hydraulic fluid to move from high-pressure to low-pressure cylinder components and back again at controlled velocities, in accordance with the various suspension modalinputs. In other words, this is a passive, reactive system driven by the inputs received by each of the hulls combined with the “mode-decoupling”. This enables the vessel to share loads across the hull contact surfaces and thus ensure a stable superstructure (the deck), optimizing vessel safety and seakeeping.
How it works