Nauti-Craft – Marine Suspension Technology

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Nauti-Craft Pty Ltd is a research and development company focused on the design and development of its revolutionary Marine Suspension System. This patented technology separates the vessel’s hulls from the deck and superstructure via a ‘passive reactive’ interlinked hydraulic system, which provides increased levels of ride comfort, control and stability. Whole body vibration (WBV) is reduced by up to 75% providing unparalleled levels of shock mitigation.

The Nauti-Craft technology is a hydraulic suspension system for multihulled vessels. The system separates the hulls from the superstructure which allows the hulls to react rapidly to wave inputs and conform to the ocean surface without transmitting high forces and accelerations of the hulls to the deck and superstructure. This provides increased levels of ride comfort, control and stability whether stationary or travelling at speed. The improvements to stability and maintaining a level attitude can be further enhanced with active control of the suspension system. This has great potential applications for commercial, military and recreational vessels.

The company

Nauti-Craft was founded by Chris Heyring to develop and commercialize a novel suspension system for marine vessels. Chris began putting into practise his concepts of a marine suspension system more than ten years ago. He first applied his thinking to a small sailing boat to test out the basic concept. This testing showed sufficient promise to embark on the development of a radical 8 meters quadmaran; then, he designed an 18 meters commercial catamaran and built a 1:10 scale model to test and further prove the viability of the system for potential Wind Farm Service Vessels. A 8.5 meters Nauti-Craft prototype catamaran, completed in 2013, has undergone extensive sea trials and tuning with outstanding results. This prototype has been utilized as a demonstration vessel in Australia and the U.K. and continues to serve as an important platform for ongoing research and development.

The creators of Nauti-Craft are Chris Heyring, Chairman of Nauti-Craft and inventor of the technology, together with Ken Johnsen, Managing Director, as well as other core members of Kinetic Pty Ltd, a very successful automotive suspension technology company.

Nauti-Craft currently holds 52 national patents and patent applications across 14 countries, with an additional one international and two provisional patent applications also pending.

The Design Process

To date Nauti-Craft have built and tested a number of prototypes, including a 4 hull craft “4Play” and most recently the 8.5 meters catamaran “2Play”. Part of the design process has been an extensive dynamic simulation program. Using specific software and proprietary dynamic models, Nauti-Craft engineers are able to calculate, analyse and validate a range of forces and motions in a range of operating conditions.
A one third scale catamaran has been used for a dynamic simulation of a wind turbine pylon docking sequence. This model includes the full hydraulic systems with active enhancement, hull water contacts, engine thrust and pylon contact and friction forces. The simulation shows the boat removing the roll and pitch components (which produce sea-sick) while its deck remains horizontal, with moderate heave motion (vertically). This is achieved using Nauti-Craft DACS (Deck Attitude Control System) which actively adjusts and maintains the horizontal attitude of the deck at low speeds and when manoeuvring relative to fixed structures or coming along side larger vessels like ships. The simulation finally shows the stabilization of the front end of the deck at a precise/given height, before touching the pylon. Once contact is made and maintained the crew can safely step across.

Benefits and applications

Marine suspension reduces slamming and jarring motions and improves comfort and safety. It reduces roll and pitch motions and improves planing speed in rougher conditions. The system gives a smaller vessel the seakeeping qualities typically found in larger vessels with much lower operating costs.

The initial design was geared to a specific commercial application – delivering maintenance crews to wind farms in the North Sea – but the technology is suitable for many others. They include small recreational craft, luxury pleasure craft, commercial and recreational fishing vessels, crew transfer vessels, oil rig support vessel, cruise ship tenders, pilot vessels, high speed military vessels, Coastguard vessels and high speed passenger ferries.

Yanmar’s “Suspension Boat Concept”

At the last Japan International Boat Show, Yanmar showcased for the first time a concept boat incorporating Nauti- Craft’s innovative marine suspension system.

Yanmar is a world-renowned maker of diesel engines with a strong reputation for its products in the marine world. It is also manufactures a range of commercial and recreational GRP boats that are manufactured in Oita Japan. Nauti-Craft and Yanmar have been working together under two successive cooperation agreements that have culminated in the concept boat displayed during the Boat Show.

The 11 meters boat was set up to demonstrate the movement of separate hulls of the boat, simulating the type of movement produced by the crossing of an ocean wave.

The main befits of the Nauti-Craft marine suspension system is up to 75% reduction in vertical accelerations (G forces) that passengers experience during travel in rough seas compared to a boat without suspension. The boat also can incorporate a feature that allows the deck to remain stable when passengers are getting on and off the boat in rough water.

Yanmar’s concept boat incorporates this innovative marine suspension system by applying the suspension system of a 4-wheel drive vehicle to a boat. The boat achieves a high level of stability with a hydraulic suspension system that absorbs wave energy. The technology delivers a smooth and stable ride during high-speed turning by actively controlling separate hulls and absorbing wave-energy. The system is expected to enhance boat safety, reduce passenger fatigue, contribute to smoother handling, and improve the accuracy of shipping schedules by reducing the impact of the weather.

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