Busy robot keeps nets clean

“NetRobot X2 is a practical tool for the aquaculturist and at the same time it is beneficial to the environment and the fish. The robot is put on a clean net and keeps it free from biofilm so that it prevents fouling,” said Yngve Askeland, development manager at Mørenot, explaining that the robot runs on a pre-programmed pattern on the net wall. The robot’s brushes thus ensure that fouling does not have time to attach itself to the net.

“Normally, fouling starts attaching itself to the net in the course of a few days. It varies a little from locality to locality – and the problem is usually greater the farther south you are,” he said, adding that the invention is intended to reduce the consequences of net flushing.

“We see that flushing is bad for the environment because of greenhouse gases as well as diesel consumption – and that this also stresses the fish. Frequent replacement of the net is a great expense that increases the risk of escape. It is better to have an automated device that runs on the net wall and keeps it clean.”

The invention is also an alternative to net impregnation, and thus a option for the industry, which is seeking to cut the use of copper-based impregnation.

“Today, copper and other heavy metals are used in net impregnation to slow down growth. The industry now wants to reduce this, and continuous brushing of the net wall is an environment-friendly alternative,” he said.

The robot resembles domestic robotic vacuum cleaners. However, the NetRobot X2 does not need to be recharged and has electric thrusters that ensure proper pressure onto the net wall. A large cage is usually divided into four zones, where the robot can manoeuvre up and down along the entire net wall.

“In the course of a day, it usually manages to brush a zone 10-12 times. The fish likes it very much. The robot is fully electric and noise-free and is operated via a cable that plugs into the power supply on side of the cage. The cable also makes it possible to transfer data. Via a modem in a coupling box on the cage, we can adjust settings from the control room, log operating time and upgrade software as needed,” he said, commenting that the development of the NetRobot X2 has taken a long time. The main challenge has been to make the robot run smoothly and remain stable against the net wall.

“It has performed well in test tanks with trips of up to 20 km. In cages, however, there are other challenges with water currents and wave movement. Getting the thruster setup to work in a stable way has been the key to success. The robot is connected to the network so that you have control over the device. In the future, there are even more opportunities,” Yngve Askeland said, highlighting both the ‘internet of things’ and the incorporation of sensors in the cage that can communicate both with robots and each other.

Today, 22 robots are operating at customers’ farms for long-term testing. The plan is to develop an operation centre that has control over the follow-up of the equipment that is in operation.

“The NetRobot X2 is not a pure quick fix,” he pointed out. “The user must have a conscious strategy about how to use the product in order for it to be a success on an equal footing with other established technology in our industry. We will have a close dialogue and follow-up with customers who are using it – and expand service and support functions along the way.”

Yngve Askeland commented that Mørenot is proud to be nominated for the Innovation Award.

“The Innovation Award is highly regarded in the supplier industry because it shows that something has been done that deserves to be noticed. It is a very competent jury who assesses the candidates, and we are honoured to be nominated,” he said.

“We expect Aqua Nor to be as big as it usually is and hope for a lot of attention about the net robot. Aqua Nor is always a busy week with many exciting meetings that we look forward to.”