Digital design technology is transforming transportation, from aircraft and auto parts to military and rescue watercraft. Now, this technology of tomorrow is tackling Olympic competitive sailing – at least on the side of the official US Sailing team.
Richard Didham – a design/analysis engineer for US Olympic Sailing Innovation, Research and Development – hopes to wring every possible performance improvement out of the many variables that affect Olympic sailing ahead of the 2020 Summer Games in Tokyo.
Working at Autodesk Technology Centers in San Francisco and Boston, as well as US Sailing’s own FAST USA technology center, Didham needs to steer the huge number of moving parts in this venture toward a single endpoint. “The three most important factors in sailing are boat speed, boat speed, and boat speed,” Didham says. “Many factors influence an athlete’s performance in a race, but if their boat is faster, it can make up for mistakes in other areas.”
In the Venn diagram of boat speed, the confluence of variables includes racing environment, tactics, human factors, coaching, and – crucially for Didham and his team – sailing equipment.
The sport isn’t what you expect if you’ve ever seen many of the iconic sailing races (or an aftershave commercial) where teams of up to 10 sailors form a well oiled machine aboard a large yacht.
Olympic sailing has one – sometimes two – crew, the craft much smaller than a standard yacht and with strict design and manufacturing constraints. “Everyone is supposed to have the same basic equipment to race with,” Didham explains, “It makes it a lot less a competition of design and more one of athletic sailing ability.”
That leaves extremely narrow bands within which designers can prototype and manufacture components, exploiting ‘really small’ differences within the rules to get incredibly marginal gains above the competition. To do that, US Sailing has invested heavily in complete system modelling, not just of the craft and performance but the entire race.
The team’s data acquisition platform (from provider SAP) is a three-stage quantitative measurement tool which combines information generated by the athletes, the equipment and its performance and deep video analysis of the race and venue.
It incorporates everything from tactical analysis and equipment performance to the style each sailor uses, and it can all be folded into a simulated VR representation of the race, a HD model for athletes, coaches and designers to pore over to design favorable tactics.
A lot of those variables – as you can imagine – are stuff sailors and engineers have little control over. But the manufacture of components can still be optimised in response to them. “We want to profile anything we can’t change to the best of our abilities,” Didham says.
“You can have lots of breeze, no breeze, a very choppy sea state, a really flat sea state. Currents vary from one venue to the next and with tides depending on time of day. It can be really difficult to know how to race in the specific set of conditions.”
Being forearmed with as much of that knowledge as possible lets the team pair the particular athlete’s style with the race’s environmental conditions and come up with the best possible vessel design to take advantage of both.
The prelude
To that end, Didham and his team has come up with The Moth. A hydrofoiling dinghy, the Moth sails using an underside wing that lifts the hull out of the water. It isn’t the craft that will compete in the Olympics but a proof of concept – the resulting R&D insights will inform directly on the optimum design for the production fleet that will compete in Tokyo.
Design, prototyping and manufacture of The Moth addresses two major areas of enquiry; optimum design for the most dynamic and efficient travel through the water, and the material science of carbon fiber reinforced manufacture. Put in even simpler terms, as Didham explains; ‘All we want it the maximum lift versus drag’.
It began with complex computational fluid dynamics software, which modelled the way bodies of water move in incredibly fine details to come up with the optimum body design.
And as we’re seeing more and more, there was a strong element of generative design involved. Numeric values for the bluntness of the hydrofoil wing’s leading edge, locations and values of its maximum thickness, the sharpness of the trailing edge and more are programmed into the algorithm (‘all we have to do is type in a few numbers’ is how Didham puts it) and a new design is generated automatically for the team in response to the criteria.
“We can create and analyze every single possible foil shape in the world, then look at the graphs and simply pick the right one,” he says. “The differences in performance from new shapes versus previous shapes start to converge and you just stop the algorithm – you have your optimum foil.”
And as the information gathered by the data acquisition platform can be fed into the generative design system as live environmental constraints, the software will be working with real-world venues and conditions.
The data is then sent to the CAD/CAM environment of Fusion 360 to model, and Autodesk Tru-Composites steps in. Coming up with the best way to enmesh sheets of carbon fiber can be just as hard as coming up with the optimum design manually, but generative design principles can also be applied to the composite manufacture.
The software determines the lay-ups of carbon fiber along with the manufacturing materials to achieve the necessary mechanical properties of thickness, tensile strength, etc.
The Moth was then sent to the CNC machine, and what might be the best-performing carbon fiber, single-person hydrofoil dinghy wing was the result.
The view from here
Today, after the lessons emerging from the design and making of The Moth, Didham’s team has its sights set firmly on the aptly named Finn rudder, the lynchpin they hope will propel the Olympic fleet to awards glory. It goes without saying it has to improve on current designs, but it also has to be customisable to the styles each specific athlete.
It has to produce low drag across a wide range of flow conditions and remain structurally sound while facing such variable loads. And it all needs to be achieved within the very strict design and manufacturing guidelines the Olympic rules dictate.
With so much at stake, the race to find any possible advantage is worth it. And as US Sailing is proving, digital design is one of the tools they hope will make the perfect racing sailer.