Pop along, and let me know what you think, will it be a Yamaha year, or will other teams be on the Yamaha pace? It’s certain that the Ducati is quick in a straight line, after seeing Stoner at the weekend, but will it work around the twists.
The VAG Direct Shift Gearbox - sometimes called the S-Tronic in the Audi range – is the world's first production dual clutch semi automatic gearbox. The system was developed for Audi by BorgWarner for use in the companies Audi TT 3.2V6, and was so well received it is now used in much of the Volkswagen Audi Group range.
The DSG is often compared to F1 style automated or robotic manual gearboxes, but differs in some very important ways.
The DSG gearbox is, however, not a new invention. The system was first designed by Andolphe Kégresse just before the second world war but because of the lack of technology, not to mention the war, he never produced a working version of the Dual Clutch Gearbox (DCG). The system was used by another German car company in the 80's though: Porsche used the PDK (Porsche Doppelkupplungs) system in their 956 and 962 Le Mans race cars, and Audi used the same system in the Sport Quatro S1. Porsche and Audi have a long history of technology sharing.
Both of these uses eventually faded, primarily because the computing technology that allows the system to work so effectively did not prove to be reliable enough in the tough and demanding world of the race car.
To understand how revolutionary the DSG gearbox is, first I will explain the F1 style systems. These differ in name depending on the manufacturer; Ferrari call theirs the F1 system, and BMW call theirs the SMG system.
These gearboxes all have one thing in common: they are just manual gearboxes, with a manual clutch that is operated by pneumatics. This method has many of the benefits the DSG box does. The gearbox itself weighs less: as the gear change is accurate, and no human mistakes can be made, the materials can be less hardy. They are also far more performant than the manual equivalent, both the BMW SMG II and the Ferrari F1 systems change cogs in around 80 milliseconds. This means that, while the gear is being shifted, all the power from the engine is waisted and a feeling of on-off-on is felt in the car as the pneumatics shift from in gear, to clutched, and then back into gear. The smoothness of this in the car depends on the software controlling it: for the fastest changes it can feel quite 'bumpy', similar to a bad gear change in a manual car. The only way of releaving this issue in the past was to fit a torque converter, this is the way that a standard auto box does it, and why it feels far smoother than any of the manual gearboxes produced. A torque converter, however, is very wasteful in terms of power, and usually very heavy.
The DSG box takes the basic idea of pneumatic clutched boxes a step further. The heart of the DSG comes from the fact it has two clutches. The basic idea being that the gearbox can then have two gears engaged at any one time, one driving the car, the other waiting to take over.
The clutch arrangement is setup for odds and evens, where clutch 1 operates the 1-3-5 gears and clutch 2 operates 2-4-6.
DSG works by allowing the software to decide what gear the car will need next, and then pre-selects it. If you are accelerating, it will have the next gear up, and likewise if decelerating, the next gear down.
The system can then watch for a change signal – this is either done by clicking the corresponding paddle by the driver, or if in full auto mode the computer – and the gearbox can then tell the currently disengaged clutch (the one driving) to engage, and at the same time tells the engaged clutch (the pre-selected gear) to disengage. In this way the driver and passengers do not experience the on-off-on feeling associated with manual gearboxes. Instead, the gear change feels much more like that of an automatic gearbox.
However, because the change happens so quickly – around 8 milliseconds – the engine can maintain drive and the losses involved in the gear change are much reduced. This can be seen visually in the video below.
The video clearly shows the benefits of the DSG vs a very quick-changing manual driver.
The DSG gearbox is obviously controlled by computer, and this adds other benefits as well, even over race-going Sequential Manual Transmisions.
The computer in the DSG box monitors many of the cars sensors, these can be RPM, speed, angle of steering input, amount of wheel spin, braking and g-forces. It can then use these inputs to make decisions on which gear the car has to be in at any one moment.
For example, if you are approaching a tight corner you may want to change down two or even three gears. The computer sees that you are braking heavily, and that steering input is being applied, and can then change down either more quickly, or skip gears altogether and shift from sixth into third in one step. This allows the driver to keep the RPM in the best range for drivability. Likewise, if driving in snow or mud, the computer sees that there is a lot of wheel spin at low speeds, it can then shift up into a higher gear to allow the wheel spin to be controlled.
The gearbox also keeps the F1 style gearbox's benefits. Because the computer will change gear very precisely, and not over stress the components, the weight of the whole unit is not much more than a conventional gearbox and clutch. This is because the parts can be made to much tighter tolerances, but still manage the same life expectancy as the manual counterparts.
There is a downside to the gearbox though: it cannot be used in races. This is because it changes gear so quickly, and the loss of drive is so minute, that the gearbox gets classed as a Constantly Variable Transmision. The FIA and other governing bodies outlawed this in the early 80s. However, with the speed that some of the current Formula One cars can now change, this may be altered. The current Honda gearbox is called the 'Lossless' gearbox after all, but they did prove that it reduces engine power and its use was therefore allowed.
The crowning achievement of the DSG is the English-made, Ricardo Company's seven speed DSG, for use in the Bugatti Veyron. That particular car is worthy of it's own – more detailed – article, so that will have to wait.
So, next time you drive a DSG car just think: You can change gear faster than even the Formula One and Indy drivers.
Special thanks to Audi for the images and the link to the video demonstrating the gearbox in action.
This is an excellent use of Flash! The 998 GT3-RS site shows the Porsche driven round a track, followed by a chase car, the cool thing however is that you can flick between camera views in realtime, and it shows the G loads on the car at all points around the track.
Brilliant, pop along to see it in action (sounds good too!)
As you all should know by now, F1-Blog is just that. Anyhow I've recently got back from the 1st day of the Silverstone Test and have a bunch of photo's from the session. Head on over for the lowdown.
The Imola GP finished with Schumi on top for the first time this year.
It was certainly a decent (if not brilliant) GP, for all the breakdown head on over to f1-blog where I have done a diagnosis of the GP.
The DVD Times is reporting that a region 1 version of a fully restored version of the great F1 movie is being released. It features a restored 65mm to DVD video transfer and a remastered 5.1 soundtrack.
It also features a bunch of documentaries, 4 of which have not been released before.
I'm not sure about a region 2 release date (or even if it's coming here) so I would pick it up from your local R1 distributor.
Where all the F1 based content has disapeared to. Then wonder no more! pop over to f1-blog.co.uk for a more in depth look at one of my passions.
It seems that Mike Gascoyne and Toyota are not happy with each other, Gascoyne has been suspended due to "fundamental difference of opinion with regard to the technical operations". What that probably means is that Toyota is not happy with the strict an open way that Gascoyne runs his team.
Toyota where rumored to be paying Gascoyne the highest wage in the F1 game for his particular services, due to the fact he transformed the Renault team in his time there.
It is said that Toyota will probably assign Pascal Vasselon the job. Toyota picked him up from Michelin at the end of last year.
Not bing privy to the conversations that have gone on between Toyota and Gascoyne I cannot comment on why the break-up has actually happened; however I think if Toyota are basing this decision on performance that they should perhaps give him a little longer as he took a while at Renault to get things as he needed them; and after all the new Bridgestones are no real match for Michelin so far this year, all Bridgestone teams have struggled. However if it is the tyres that are causing the issue, there will be nobody better placed to forward the development of a fix than Vasselon.
Just a few things on the F1 front.
Prodrive have submitted an entry for the 2008 season, that makes 13 teams now with an application submitted, Bernie says only 12 teams can race, so who will not make it? (oh Minardi have submitted an entry as well).
Davidson (Honda) has again topped the running in Australia in practice one and two. Although the lower temperatures have caused issues with some teams.
Oh and yes, it's on at 3:30am UK Time so set the alarms
Some good and some bad news from this weekends motorsport.
I’ll start with the bad, IRL (Indy Racing League) had a bad start to the season, losing Paul Dana in a crash on Sunday morning during practice. The crash happened on the exit of turn 2 where Dana unfortunately crashed into the back of the already demolished Ed Carpenter car. My thoughts go out to all of his loved ones.
On a more positive view the MotoGP season kicked off in fine form. The opening race finished with Ducati and Capirossi taking the top step followed by little Dani Pedrosa second, and the American Nicky Hayden on the third step. Where was Rossi? he was unfortunately tagged by Ellias at the first corner and ended up 14th after starting the race over a minute down on the leaders, with a damaged Yamaha. It should make for an interesting season!
The WRC headed for the sun of Spain as well (the MotoGP was also held in Spain). This season sees the battle between Loeb and Gronholm intensify, and now that Gronholm has a car to back him up it looks like it will be interesting. Both of the works Ford’s suffered Turbo failures on day 1 and dropped Gronholm and Hirvonen back in the times, Gronholm did well to battle through the remaining 10 stages with 7 of them being stage win’s. Well done to the Skoda drivers with 3 of the 4 cars finishing in the top 10.