March 1, 2010
A small unmanned submarine with cutting-edge manoeuvring and sonar capabilities is set to dive into new commercial and defence markets.
St. John's-based Marport Canada Inc., which builds sonars for commercial deepwater fishing, is releasing its SQX-500 submarine. The submarine was built with NRC help and is suited for use in defence, offshore energy and ocean science applications.
The story starts in 2005, when Marport CEO Karl Kenny conceived the idea of using software to define the function of a sonar device, rather than building a dedicated piece of equipment for each type of application.
"We thought, 'Why don't we build one platform that would cover a wide range of applications in our area?'" says Neil Riggs, Marport's vice-president of research and development. "As we explored the idea, we realized there were other markets we could get into besides fishing."
Marport's unique software-defined sonar uses pre-programmed computer modules that plug into a single piece of standard sensor hardware. Until now, each individual type of sonar has been designed as a separate piece of electronics hardware.
Thinking about uses for the device, Kenny reasoned that an autonomous underwater vehicle (AUV) — basically a robot submarine — could carry the sonar system into new markets.
The first thought was to build a vehicle to "fly" a side-scanning sonar above the ocean floor to map routes for subsea cables and pipelines. In order for the images to be usable, the AUV would have to be stable. Kenny suggested that if it could be made stable enough, and could also hover, it could take on further roles such as underwater inspections. In 2007, Marport decided to develop its own AUV.
"At that point I remembered that I knew people at the NRC Institute for Ocean Technology in St. John's who were involved with this kind of work," says Riggs.
NRC had an underwater vehicle development team. Marport had an innovative sonar technology. They joined forces to develop the SQX-500. NRC suggested using an inherently stable twin-hull design pioneered at the U.S.-based Woods Hole Oceanographic Institution, and, with Marport, developed a combined propulsion and steering gear to give the little sub unique capabilities.
"The basic idea came from NRC," says Riggs. "It has really evolved, but NRC was an important partner at the beginning and is still very much part of the project. We have a nice little vehicle now, and Memorial University of Newfoundland has joined the development team."
The vehicle is a twin-hulled submersible with two 1.6-metre long, 23-cm diameter hulls that hold sonar, batteries and navigation electronics. Joining the top and bottom hulls are a pair of rudders, each supporting a motor, thrusters and horizontal winglets that provide power and steering.
The "vector thrustering propulsion control system," prototyped in NRC's test tanks in St. John's, and jointly patented by Marport and NRC, gives the machine high manoeuvrability and a helicopter-like ability to hover.
The SQX-500 can dive to 500 metres, but Marport already plans a model for 3000 metres. In addition to civil uses, the company will work with General Dynamics Canada to develop the AUV for defence roles such as anti-mine countermeasures.
Plans for the future: a swarm of SQX vehicles operating under the ice. Graphic courtesy of General Dynamics Canada Ltd.
Riggs sees many essential but low-profile uses for an SQX-type of vehicle, such as mapping routes for underwater oil and gas pipelines or power cables, or inspecting underwater parts of offshore drilling platforms.
Riggs says that in the future, AUVs will work in swarms — each independent, but communicating with the others to cover various tasks in an overall mission. In the nearer term, he hopes that SQX-500 swarms will be used to map the Arctic seabed.
"If we have one great ambition," he says, "it's to have our vehicle used in the Arctic, under the ice."
