What we know about Formula 1's 2020 cars so far
Formula 1's 2020 cars may not yet have run in anger on an official grand prix weekend, but pre-season testing and the build-up to Melbourne has already offered us a good glimpse at what teams have come up with.
And, while many had expected this year to be like a holding pattern before the bigger revolution that was originally coming for 2021, the reality is there has been plenty of exciting technical developments unleashed.
So while F1 faces an enforced break because of the coronavirus pandemic, we take a look at the key developments that will be key to look out for when track action resumes.
DAS and PAS
DAS was by far and away the single biggest talking point of the pre-season test, with both Mercedes drivers unconventionally pushing and pulling on their steering wheel to affect the direction of the front wheels.
However, what we've discovered since is even more fascinating, as it turns out that DAS was simply a system that overlaid another that Mercedes and Ferrari had used in 2019 – PAS.
This 'Power Assisted Steering' is a variable Ackermann system that makes it possible to angle one wheel independently of the other, depending on steering input.
It was run by Mercedes throughout 2019, with Ferrari installing its own version for the French GP. The Haas VF20 also has the Ferrari PAS system onboard and was hoped would help it solve some of the front tyre temperature issues it faced during 2019.
Haas makes some interesting changes
Staying with Haas for the moment, it's interesting to see where it has focused its efforts around the car to try and overcome the issues it faced in 2019.
Haas F1 Team VF-20 diffuser
Photo by: Giorgio Piola
One such area that's seen the team spend time and resources developing is the floor ahead of and around the rear tyre. The tyre squirt deck, as it's known, is a particularly sensitive area of the car, as changes here can lead to big gains from the diffuser.
The reason it's so sensitive is that the airflow becomes turbulent as it's spilt off the tyre and, as the tyre's sidewall is forced to deform under load, it squirts this turbulence into the diffuser's path, disrupting the flow through it and robbing the car of downforce.
This is why we see teams use a multitude of flow conditioning solutions ahead of the rear tyre, including fully enclosed holes in the floor, angled slots, flaps, strakes and winglets, as they attempt to manipulate the flow stream and reduce the tyre squirt phenomenon.
Haas put some effort into this area of the car during its development phase during 2019, as it first introduced a twin vertical strake arrangement at the British GP, whilst also revamping the stack of vanes on top of the outer edge of the floor.
For 2020, the designers have looked to further inhibit flow into the diffuser's path by adding slots in the region between its wall and the two strakes, injecting more flow to the underside of the floor to desensitize the turbulence created by the tyre.
Red Bull goes its own way
Red Bull may well have understood the PAS system itself last season but, for whatever reason, decided it would go its own way for 2020, as the RB16's front-end is a treasure trove of technical endeavour.
It has flipped its suspension on its head for starters, opting to use a multi-link wishbone arrangement for the lowermost element in 2020, rather than the upper as it did in 2019.
The rear leg of the wishbone , is not directly connected to the front leg  which also features the novel arrangement of passing through the chassis.
These changes have coincided with the drastic repositioning of both their steering rack and steering arms to a more rearward site, requiring a holistic repackaging of every steering and suspension component and its 'S' duct solution.
It's clear that such effort is driven by a desire to improve several aspects of the RB16, from its ability to extract the maximum from the tyres to its aerodynamic output.
Red Bull has incorporated fins on top of the cockpit transition and added a large flap under the airbox as it looks to use both to improve flow around the cockpit, halo and airbox region for 2020.
Meanwhile, at the last day of the pre-season test, it introduced bodywork with inlets in the region alongside the cockpit, improving cooling on the RB16.
Ferrari has also looked for gains in this area, opting for some 'Viking Horns', a solution we first saw back in 2005 from McLaren.
This has been made possible due to the narrow trapezoidal airbox design preferred by the Scuderia, as the viking horns on the SF1000 simply occupy the space left over that's permitted for bodywork in that region by the regulations. This means that the likes of Mercedes, who have a particularly wide airbox, couldn't use these.
McLaren's main focus
McLaren MCL35 front wing detail
Photo by: Giorgio Piola
McLaren has made a concerted effort with its front wing this year, making numerous changes to the overall shape of many of the component elements. However, where it has made the biggest change is with the footplate.
As shown here (red arrow) the footplate now has a bluff L-Shaped Gurney trim that runs around the outer edge.
Capturing the airflow and creating a pressure gradient, this solution will help to pull on the surrounding airflow and help to draw it across and around the face of the tyre, reshaping the wake turbulence created by the wheel and tyre that's ordinarily damaging to other aerodynamic structures if left unchecked.
Alfa's rear wing push
Alfa Romeo Racing C39 rear wing pillar detail comparison
Photo by: Giorgio Piola
Alfa Romeo arrived at the second test with a new rear wing solution that saw the height of the swan-neck style rear wing pillars extended considerably when compared with the usual specification.
The Swiss team has taken further advantage of a vagary within the regulations that never intended for the swan-neck style pillars in the first place.
They are allowed as they're within the region that's 100mm from the car's centreline, which intended for them to be joined to the underside of the mainplane.
However, with teams having realised that they could lessen the aerodynamic impact using the swan-neck design, they're now a universal design feature.
Alfa Romeo's use of these much taller swan-necks will not be for structural purposes but aerodynamic ones, with the enlarged surface area likely used to improve the wings performance in yaw, whilst also having an impact on the operation of DRS.
It's not the first time we've seen such tactics deployed though, with BAR exploiting a vagary in the regulations back in 2004.