Parked next to Liverpool’s rain-soaked docks under a moody grey sky and the watchful eye of the Liver Birds, the BAC Mono looks like it could have been driven straight out of a Gotham City panel – not a Speke industrial park just shy of 10 miles up the road.
Just like that unconventional, distinctively Northern England backdrop, which blends effortlessly with the Mono’s black and silver aesthetic, this single seater supercar is uninterested in the mundane functionality of your typical set of four wheels. No, this vehicle, as Briggs Automotive Company (BAC) Co-founder and Director of Product Development Ian Briggs recently told TCT, was designed purely for the sport of driving.
“We don't have to think about any other function for this product other than, a guy's going to get in it and he just wants to drive, he doesn't necessarily even want to go anywhere,” Briggs says of the Mono’s niche demographic; the kind of customer who might already have half a dozen hypercars tucked away in their garage. “For us, it's a really simple focused target and that is to reduce weight, increase power, get the mass towards the centre of the vehicle, get the mass as low as we can.”
Building on design DNA first seen on the company’s Mono R last year, the new Mono is lighter than its predecessor and boasts a higher performance figure of 332bhp thanks to a 2.3-litre four-cylinder turbocharged engine and over 400Nm of torque. With a design brief set to make the car “visually lighter, cleaner and more simplistic,” each body panel, all re-engineered to reduce visual mass, features graphene-enhanced carbon fibre to decrease weight and enhance strength.
The subject of weight is something BAC has been focused on in an ongoing partnership with software developer Autodesk since 2014; if you’ve ever attended an Autodesk University London event, you will have likely seen some generation of the Mono parked outside, usually surrounded by keen selfie takers. The most recent product of this collaboration can be found in the alloy wheels of the new Mono which have been generatively designed to speed up the iteration process and reduce weight, offering big benefits across acceleration and performance.
“The best place to save weight on the car is the tyre. The next best place is the wheel,” Briggs said, explaining the thought process behind the Mono’s latest iteration. “But given the Mono was quite well optimised in that respect anyway, we took a clean sheet, looked at everything and started with the most important part which was develop a new tyre with Pirelli. Next was our carbon wheel. We want to save weight at the rim rather than in the centre of the wheel initially but once you’ve got all the weight out of the rim, then we want to start concentrating on the spoke design, getting as much weight out of that as possible.”
The new BAC Mono parked on Liverpool's waterfront.
The team worked with Autodesk Research to determine how generative design in Fusion 360 could be applied to quickly explore design outcomes, taking into account real world performance criteria, standards testing data from British wheel manufacturer Dymag (previously used to manufacture and certify other BAC models for road use), manufacturing methods and materials, and BAC’s signature aesthetics.
“We could straight away, within a matter of hours, see the most optimised version of that wheel. Then we can come back from that and decide if we want to go to that level of complexity. Do we want to simplify it? Does the design department have something to say about how it looks?” Briggs explained. “We could kind of come back to it rather than work from the other direction where you start off, you're always making steps towards little improvements each time and then just deciding how long you keep going through that process.”
Starting with key performance needs and manufacturing constraints in mind, this technique almost allows engineers to work backwards rather than going through an extensive iteration process to reach the optimum result. It’s a method that has already been deployed in the automotive sector by the likes of General Motors to redesign a seat bracket with a 40% weight reduction, followed by Volkswagen, which last year used generative to reimagine parts of a 1962 classic microbus. Speaking about the benefits of generative design and Autodesk’s involvement in the BAC project, Andy Harris at Autodesk Research said:
“If you look at the traditional way of an engineer designing, they're going to focus down on maybe one, two, three designs that kind of meet the requirements whereas with generative design, what we're trying to do is get the computer to actually design a large range of designs that you can explore and then choose from. What we did very differently with BAC, which is very interesting to me from the research point of view, is where we normally would look at the performance, the mass and the cost, which generative design as a product gives us, we wanted to also explore aesthetics as a fourth dimension. So, with a lot of guidance from BAC on brand identity and the kind of aesthetics the final design had to have, we were able to basically direct generative design in a way that it generated a large cluster of designs that all were very similar in aesthetic look.”
Generatively designed wheel, created in partnership with Autodesk.
Different manufacturing methods were tested and CNC milling in aluminium was ultimately identified as the best option with the team going from 3-axis to 5-axis milling at Autodesk’s Birmingham-based Technology Centre. The result was a redesigned 2.2kg wheel alloy finished in BAC’s signature ‘gunmetal grey’ that’s 35% lighter and compliant with stringent European structural regulations. The total wheel weight is now 4.7kg for the front wheels and 4.9 kgs for the rear, including both the alloy and carbon rim.
“We actually [3D] printed three wheels about a third scale,” Ian explained. “We printed them in plastic and we said this is the current one, this is the optimised one for 3-axis machining, this is the optimum for 5-axis machining and this is the optimum if we decided to print the wheel. Now I can see if I 3-axis machine I only save about 250g, if I 5-axis machine I save 1.2 kgs, and if I 3D print it, I’m only saving 1.5 kgs. You very quickly get that overview to say, well, that's all that’s possible anyway but I've just increased the price by 10 when I can get three quarters of the way to it and still have an affordable product. It’s a completely different way of understanding how far you can and should go. That was a big revelation.”
Andy added: “It really helps you accelerate that concept design stage and we really noticed that with BAC, where we were talking about this project towards the end of last year, and within the first couple of months we got the design ready for manufacturing, which from a wheel development point of view is phenomenally fast.”
It isn’t just the wheels where the addition of new technology has led to a reduction in weight. The new Mono weighs just 570kg thanks to a number of enhancements in graphene and end-use additively manufactured parts, the latter of which came as a surprise to Briggs. In-house 3D printing capabilities are a fairly recent addition to the BAC shop floor following a meeting with global science and materials company DSM where a Novamid CF carbon fibre 3D printed motorcycle brake lever with properties similar to that of cast aluminium helped make that “mental leap,” as Briggs puts it, to see 3D printing as a production tool. Now, the Mono has around 40 3D printed end-use parts installed.
The generatively designed alloy is now 35% lighter.
“Straight away I can see it [3D printing] on every metal component on the car,” Briggs says. “We've got 3D printed plastic parts now that are supporting things like electronic control units or even supporting things like the wiring harness. The car's got a solid mounted engine, you can’t have any unsupported wiring in the car, it vibrates and eventually it fails. So we strive to support wiring everywhere on the car in these places and we make little 3D printed parts now to do that.”
While much of BAC’s previous AM work has been outsourced to UK service providers like Malcolm Nicholls, which produced a number of prototypes on the RPS NEO 800 last year, the BAC garage now houses an Ultimaker S5 desktop 3D printer with a closed build chamber from 3DGBIRE, enabling BAC to leverage high-performance polymers from DSM via Ultimaker’s Material Alliance Program. In addition to prototyping and R&D, those end-use parts, some of which have been printed using HP Multi Jet Fusion, include the front and rear light surrounds, mirror arms and mirror housing, front hatch hinges, engine inlet components and more; the kinds of parts were the cost of an injection mould tool just wouldn’t be economical for such low volumes. Adam Mughal, Lead 3D Designer at Briggs Automotive Company recently described how BAC has managed to get the cost of the car’s wing mirrors down from 60 GPB to just 10 GBP by 3D printing them in two parts. Those volumes however, do lend themselves well to customisation and there’s scope to use 3D printing to add features such as bespoke name plates or part numbers which are personalised to the customer.
More on 3D printing in automotive:
- Winning the manufacturing race: Brad Keselowski on 3D printing, motorsport and the need for speed
- Full throttle: Desktop Metal on automotive manufacturing's new paradigm
- The Ultimate Printing Machine - How BMW is applying 3D printing to commercial vehicles
Briggs says he feels the term ‘rapid prototyping’ had “really undersold the technology [3D printing]” in the past. While he cautions that metal 3D printing, even for a luxury product working to extremely low volumes, wouldn’t be the most thrifty method of manufacture for something like the Mono’s wheels, he believes there could be a place on the Mono for metal additive coupled with generative design in the future.
“Over time, it's something we'd certainly like to look into,” Briggs says, suggesting a titanium support for the exhaust system might be an interesting test project. “I can imagine many of the suspension components, many components on the car could be printed once it becomes affordable and I have to say, our low volumes and our high price points, we're one of the first companies who can adopt those types of technology because we can afford a high piece price in exchange for not having any tooling costs.”
Building on the revolutions happening elsewhere in the automotive industry across drivetrain and autonomous vehicles, the way we think about cars as transport is changing. The same can be said for cars as a luxury product. Their customers, like BAC, are in constant pursuit of perfection and the latest and greatest. Briggs recalls demonstrating the new wheel design to a customer who was left stunned upon realising they could pick it up as easily as a glass of water. “They like to be blown away by all that,” he adds.
Briggs says the team has a roadmap in mind for how the car might look in future models and while generative design is only a small part of the Mono’s style today, given its unique structural and aesthetic qualities, that might not be the case for long.
“There are a lot of revolutions coming in the car industry, and with generative design, to change how cars are designed, engineered, built and look. It's a super exciting time in the car industry […] it’s a challenging one but I think it's super exciting.”
