European Aquaculture and Fisheries today face several challenges including increasing competition from North America, Canada, New Zealand and Japan. Increasing costs for land and water which may in the near future force aquaculture installations to move further offshore where the risks of losing or damaging fish stock due to damage of the ropes during heavy storms are higher. Damaged ropes or cages results in high costs of replacements, loss of fish, environmental and H&S issues. Damage to mooring ropes during strong storms and subsequent snapping of the ropes that hold the cages are the cause of 76% of loss of fish stocks.
Our primary market is the EU fishing industry, a major source of employment and food providing more than 7.5 million tonnes of fish and employing over 526,000 people of which 88% work within the SME community.
SMEs in aquaculture, fishing, shipping and ports industries need to increase efficiency and safety as well as reducing the environmental effects in order to become more competitive. The current methods used for inspection of ropes are subjective and hence a need exists for a rigorous quantifiable assessment method. A mooring rope snagging while under stress produces a dangerous backlash which could potentially cause injury or even death. Fishing net snagging due to overloading results in lost catch and the need to re-trawl, wasting additional fuel. Damage to mooring ropes holding the aquaculture cages could result in snagging of the ropes and therefore loss of the fish stock with its economic consequences.
The Smartcatch Project developed a Nitinol wire based non-contact stress sensing system for mooring and fishing ropes with a load force that will depend on the characteristics of the particular application.
This has been combined with a control and software system suitable for installation on mooring ropes holding the cages used in the fish farming (aquaculture) industry and net or mooring ropes used in the fishing industry.
The system is capable of sensing deviations in rope loads and of giving an accurate quantifiable assessment of the state of the ropes. The Sensor Wire to be used is a specifically heat treated Nitinol wire which undergoes a large change in electrical resistance for applied stress. It has been integrated into the mooring and fishing ropes and as such allows interpretation of the stresses and degradation of the ropes. Nitinol is a Nickel-Titanium Alloy with close equal atomic percentage proportions of Nickel (50-55.6% by weight) and Titanium.
The benefits of the Smartcatch project on available methods for measuring strain are that the system will be able to cope with hostile environments that are normal operating conditions in the aquaculture and fishing industries. The Smartcatch system provides a continuous monitoring and real time response. This is possible due to a combination of Nitinol and the non-contact sensing device, Nitinol has negligible temperature sensitivity once is has been heat treated to the desired characteristic and therefore produced repeatable stress measurements. The system provides a large change in resistance which is linear to the strain and this produces a reliable reproducible stress measurement.