This new gyroscopic stabiliser looks to cater for boats from 30 to 80 ft.
The growing field of gyroscopic stabilisation in the pleasure boat world has always been the reserve of Seakeeper. For the last two decades, US-based Seakeeper have taken gyro vessel stabilisation for the private boater from a concept to reality. However, there is now a new contender in the form of Smartgyro.
This Italian company is rolling out a series of gyroscopic stabiliser systems to cater for boats ranging from 30 to 80 ft. Their first two models in production now are the SG40 and SG80. The SG40 is for craft between 50 and 60 ft, while the SG80 will cater for boats between 60 and 70 ft. The SG20 will be available early next year, built for the 43 to 50 ft sector, and following that, in the not-too-distant future, we are told that the SG10 will be offering an even keel for owners of boats down to 30ft.
Gyroscopic stabilisation has proven popular in recent years, especially with Seakeeper pushing this concept right down to boats 23ft in length with their compact DC-powered Seakeeper 1 system. It is hard to put a price on not having a green face, especially when working at sea for long periods, and gyros, unlike fin stabilisers, have no external appendages creating drag – you just need the space to be able to fit one.
How does it work? Well, like any gyroscope, it resists force trying to move it off its spinning axis. If you push the top of the gyro forward in an action known as ‘precession’, it will exert force on the port side. Pushing it aft will reverse this effect to the starboard side. With the gyro in its locked position, unable to rock either way, it is ineffectual. The key is the timing of its precession. A stabilisation system is controlled by a roll sensor. An ECU then controls the whole operation by interfacing electronic intelligence with hydraulic power. Hydraulic power comes in the form of a hydraulic pump, generally controlling four hydraulic rams. These rams control which direction the gyro tilts in, how far it tilts and how fast it tilts. The system has the ability to assess the wave pattern in order to act proactively. The limit of the fore and aft precession is determined by the amount of travel permitted by the hydraulic rams, so there is a limit to the duration of each thrust of the gyro. Precession speed also affects the amount of stabilising force produced, so if the gyro precedes fast it will have a short but powerful effect. To reduce temperature and increase efficiency, the gyro chamber is a sealed vacuum, thereby removing air friction. A seawater cooling system runs through a sealed fresh-water heat exchanger, which, with the SG40, can be a flow rate of up to 8gpm.
The SG40 system runs either off 230V AC or 24V DC power. Though it has not been confirmed, I suspect the DC power is provided through an inverter, so the reality is that you will most likely need a generator to provide the 4kW it needs to ‘spool up’ to its lowest effective stabilisation speed. It will take 25 minutes to reach this point, after which it then needs between 1.5 and 2.5 kW to run. After 55 minutes it is at full power, producing a massive 19,000Nm of anti-rolling torque ‒ enough to keep an anchored 60ft flybridge boat stable overnight. Not surprisingly, it is no lightweight, weighing in at 650kg, and with a footprint of 0.86m x 0.93m. Noise levels are claimed to be 68‒70 db at 1m, which once enclosed in a soundproof cavity will not be intrusive.
Like Seakeeper, Smartgyro have started at the top end of the scale and are working downwards. This all-powerful technology is expensive and, we can suppose, easier to develop in big packages. However, the middleweight market has proven very popular for gyros, so it would not be unrealistic to suppose that we will see Smartgyro’s SG10 and SG20 in the marketplace by the end of next season.