Winners of the Maker Games at the University of New South Wales (UNSW) last year, team Arash, talk to PACE about the technology behind their autonomous naval ship hull cleaner.
UNSW’s Maker Games 2018 completed its second year in October, showcasing the innovative projects of undergraduate students. The winners this round were Team Arash, a group of four third-year engineering students in their third year at the university.
The students – Tom Grimes, Evan Pignatelli, Edwin Lipman and Kiel Allen – responded to the challenge set by defence industry group BAE Systems to come up with a way to make the process of cleaning and painting of naval warships cheaper, safer and more efficient.
“The competition was pitched to a few of the students in lectures and online. Kiel, Tom, Ed and I have been good mates since our first year of university, so we decided to form a team and scroll through the different projects that make up the Maker Games and determine which one we wanted to do,” Pignatelli told PACE.
“From there, we decided to do the BAE Systems project, which was the ship cleaning one. We had to develop a two-page pitch and video to submit to BAE Systems and they would in turn select us to do the project.”
BAE Systems presented the team with a problem – how to effectively automate ship cleaning, inspecting and painting processes. Traditionally, these tasks are carried out manually, with the vessel lifted into dry dock while maintenance staff carry out the arduous work in often dangerous conditions in a process that can cost $250,000 a day.
Team Arash went through several ideas in an effort to come up with a solution to the problem. “That’s what the development phase of the competition was – developing a prototype that proves this problem can be solved,” Pignatelli said.
Pignatelli said some of the team’s early ideas were not so successful. “At the start of the competition, we sat down and thought of all these different ways to solve the problem. Our first idea was a window cleaning hoist that moved around – it wasn’t an especially good idea, to be honest.”
It was when the team began to think about the kind of adhesion mechanism that would be required when the idea of using magnets came up.
“We thought, ‘What if we can use magnets at a certain distance from the hull to create an attractive force between the robot and the ship but not make it stick there?’” Pignatelli said. “After we played around with this idea, we developed an initial prototype and we figured out that it works pretty well. We took it further to make the final prototype.”
The robot – called the Autonomous Magnetic Attraction Robot (AMAR) – is fixed with magnets, creating an attractive force that enables the robot to move around the steel hull of a vessel without sticking to it. Motors with encoders attached were fixed to the robot so that, as the motor spins, it lets out a pulse. “There are a set number of pulses per rotation of the motor. From these rotations, we are able to determine the distance the motors have travelled as well as their velocity,” Pignatelli said. “We used this setup to code into the system the path we wanted the device to take.”
For painting and cleaning, the prototype featured hose nozzles on the front of the device, enabling it to spray water (in this case, a simulation of high-pressure water) as it moved forward across the hull to remove barnacles.
Painting nozzles were located to the side of the device, enabling it to paint as it moved down the ship.
“The high-pressure water nozzles that we used, and whole systems, were expensive. We had a small budget, so we couldn’t afford to test it. We instead calculated the reaction force high-pressure water would create and then adjusted the level of magnetism the robot needed to hold on to the hull,” Pignatelli explained.
Because the whole team is made up of mechanical engineering students, Pignatelli said it was a challenge learning to develop the electronic systems that the device required. “I was responsible for the electronics and it was quite challenging because, up to that point, none of us really knew about electronics and coding, so we had to teach ourselves how to do it,” he said.
“With the encoder systems, as you run the electric motors, they should in theory be spinning at the same velocity, but due to inaccuracies in the hardware you’ve got in the system, they might spin at different speeds, steering the device in a different direction instead of going straight. It took a bit of work, but we overcame the issue by developing
a control system where all the motors try to match the velocity of one of the other motors so that they would spin in a straight line.”
The team was named after their academic supervisor, Dr Arash Khatamianfar, who they met with two to three times a week. Pignatelli said that his help was crucial to the project. “He is a passionate and inspiring educator who was vital to the success of the electronic aspects of the design.”
Team Arash would also meet once a fortnight with a representative from BAE Systems who would point out issues that the team had failed to address and give insights into how the process of cleaning a naval ship actually worked. “He was very good at helping us develop a better understanding of the problem we were trying to solve,” said Pignatelli.
It took 13 weeks from the beginning of the competition to the completion of the final prototype – a whole semester. “I didn’t get a lot of other course work done in that time because I was focussing on the Maker Games,” Pignatelli said. “I think competition was so challenging and yet so engaging that were happy to devote extra time to doing the best we could.”
When it came time to present their project, Pignatelli said that his team were one of the few that demonstrated their product on the night. “We were one of the only teams who had our prototype up and working properly. I think that’s one of the things that got us over the line to be honest,” he said. “It actually went pretty well. We made sure we did lots of practice runs to make sure we had it all right. It was pretty nerve-wracking being on stage and demonstrating how the AMAR worked because so many things could’ve gone wrong. But thankfully everything went smoothly.”
Part of the team’s prize was a week- long trip to the United States to connect and network with UNSW alumni working in Silicon Valley, as well as other entrepreneurs. Pignatelli said
that he and his fellow teammates are considering taking their collaboration forward in the future, but, for now, the priority is finishing their engineering studies.
“The main thing that’s stopping us is that we’ve still got our degrees to finish. We still have one or two years left. The main thing that’s motivating us to consider going forward with a start-up is the experience we’ll gain as a result of the process. It’ll be very difficult, but we think it will be very rewarding at the same time,” Pignatelli said. “We’re in talks with the university at the moment regarding its program that supports students wanting to become entrepreneurs. So, there are a lot of things we’re discussing at the moment.”