16 replies to this topic

[vandorpen]

I'm an automotive photographer living in the Netherlands. For my next personal project I have something special in mind: one of the most beautiful cars ever made — the Mercedes 300 SL Gullwing — driving on one of the most extraordinary racetracks ever — the AVUS in Berlin.

To be more exact, the car will be driving on the 'Nordkurve', an extremely fast and dangerous curve with a banking of 43,6 degrees. The track, essentially the first Autobahn, became well-known because of the highly succesful Silver Arrows. I think it will be great to see a descandant of the Silver Arrows driving on the Nordkurve at high speed.





Unfortunately, the Nordkurve was demolished in 1967 because it was considered too dangerous. That means it's not physically possible to drive a Gullwing on that particular curve anymore. Nevertheless, it can be recreated using CGI (computer generated imagery) techniques. I will render a 3D track and combine that with a photo of a 300 SL to end up with a composite image.



In order to make the Nordkurve as closely to the original as possible in the 3D software, I did a lot of online research and collected 150+ images (both color and b/w) from a lot of angles. There's only one thing I'm still looking for, and that's technical drawings and/or measurements of the Nordkurve. Considering the wealth of information on this message board, I'm hoping that someone could provide me some useful information. Would be very grateful for any help!

Thanks in advance.

P.S.: The 300 SL has raced on the AVUS, but I could only find a photo of them racing on the Südkurve. If anyone has photos of a 300 SL on the Nordkurve, I would love to see that.

P.P.S.: To give you an idea of the kind of work I make, this is my most recent piece.

Edited by vandorpen, 21 March 2013 - 14:08.

[David McKinney]

I think one of the Avus books I used to have, but no longer do, had drawings and/or measurements. There were certainly a lot of photos taken during the construction

[vandorpen]

I think one of the Avus books I used to have, but no longer do, had drawings and/or measurements. There were certainly a lot of photos taken during the construction

Thanks for your reply David! Do you know the name of the book? Found around 5-10 photos of the construction in 1936/1937, there's probably a lot more out there.

This is what I already collected:

A historical aerial image from 1953 provided by Google Earth which should help me getting the bend of the curve spot on:



And two additional images:





The last one is probably too small to be useful.

What I'm actually looking for is a cross-section of the curve. It's probably not too hard to estimate it from the photos, but getting it 100% right has my preference.

Edited by vandorpen, 21 March 2013 - 12:03.

[uechtel]

Hm, while I have much respect for your craftsmanship and the aesthetics of such pictures, I have to admit that I have quite mixed feelings about the project as such. I wonder whether in a couple of years it will still be possible to use photos as a base for historical research. Or to say it differently, how many cars will have 'uprated' race logs, which get 'proof' by such photos.

But I know my opinion will not prevent anything and whatever will be electronically possible will be done.

P.S.: The 300 SL has raced on the AVUS, but I could only find a photo of them racing on the Südkurve. If anyone has photos of a 300 SL on the Nordkürve, I would love to see that.

I think this must be 1956 as I do not know of another occasion of the Gullwings running on the Avus circuit. In that year they were running in the GT category, so 'production' models driven by privateers. If I am correct then car #42 is of Swedish driver Martensson. Unfortunately no pictures from the cars in the Nordkurve, I found only some shots beneath when Frankenberg´s Porsche crashed into the line-up of the 300 SLs.

http://gpmotozone201...ntrei-esta.html

Last remark, the name is 'Nordkurve', so no 'Umlaut' in that, just like Südkurve...

[vandorpen]

Hm, while I have much respect for your craftsmanship and the aesthetics of such pictures, I have to admit that I have quite mixed feelings about the project as such. I wonder whether in a couple of years it will still be possible to use photos as a base for historical research. Or to say it differently, how many cars will have 'uprated' race logs, which get 'proof' by such photos.

But I know my opinion will not prevent anything and whatever will be electronically possible will be done.

Thanks for your comment. Totally agreed! It has little to do with photography, it's more like a digital painting with photographic realism. It is not meant to be considered as a true to life photograph, but more as an aesthetically pleasing image (that's the goal at least...).

I think this must be 1956 as I do not know of another occasion of the Gullwings running on the Avus circuit. In that year they were running in the GT category, so 'production' models driven by privateers. If I am correct then car #42 is of Swedish driver Martensson. Unfortunately no pictures from the cars in the Nordkurve, I found only some shots beneath when Frankenberg´s Porsche crashed into the line-up of the 300 SLs.

http://gpmotozone201...ntrei-esta.html

Indeed, it's probably just a coincidence that a photo of a 300 SL on the Nordkurve is so hard to find.

There are (at least) two occasions when they raced them, according to RSC:

- Avus [GT+1.6] - 1962
- GP Berlin [GT+2.0] - 1956

Last remark, the name is 'Nordkurve', so no 'Umlaut' in that, just like Südkurve...

My bad, should've known better. Fixed it, except for the post title.

[David McKinney]

Thanks for your reply David! Do you know the name of the book?

No, sorry

[fbarrett]

Rather than computer-simulate it, why not drive a real 300SL around the "wall of death" at the DBAG test track in Stuttgart-Unterturkheim? I've done it in several vehicles, including a 1927 SSK driven by Jochen Mass and a 30-passenger tour bus!

Frank

[vandorpen]

Rather than computer-simulate it, why not drive a real 300SL around the "wall of death" at the DBAG test track in Stuttgart-Unterturkheim? I've done it in several vehicles, including a 1927 SSK driven by Jochen Mass and a 30-passenger tour bus!

Frank

Considered it, but nothing compares to the AVUS in my opinion. Plus it's a nice challenge to become really familiar with the software.

[vandorpen]

So... I guess no one has dimensions/technical drawings of the Nordkurve?

[kayemod]

Plus it's a nice challenge to become really familiar with the software.

Absolutely no offence intended, but there speaks a child of the 21st century...

[Doug Nye]

So... I guess no one has dimensions/technical drawings of the Nordkurve?

For the Curve's georgaphical footprint, scale it off Google Earth. The Curve radius is remarkably small, which explains the banking's necessary height.

DCN

[ray b]

has a land surveyor we set targets for photos at known points
photo's have to be indexed to the known set targets and printed on a tilt table
to position the targets properly
to be good to use for correct scaling plans

so a unknown photo [with out tilt or targets used]
may not be real near dimensionally correct

btw the GPL guys have a version of avus or three for the sim
the guys who built the track[s] should have a bit of research done

[RStock]

You might try searching the German Federal Archives


http://www.bundesarc...e/index.html.de

[Sergio]

[quote name='vandorpen' date='Mar 21 2013, 11:13' post='6183833']

In order to make the Nordkurve as closely to the original as possible in the 3D software, I did a lot of online research and collected 150+ images (both color and b/w) from a lot of angles. There's only one thing I'm still looking for, and that's technical drawings and/or measurements of the Nordkurve. Considering the wealth of information on this message board, I'm hoping that someone could provide me some useful information. Would be very grateful for any help!


Here are my suggestions:

1. LOCATE THE ARCHITECT'S DRAWING - I have found that I get the most and best results when researching a German topic when I search using the appropriate German words using www.Google.de - so use Google Translate to provide the German for say, "AVUS bank angle" or "AVUS circuit construction drawings" and search for those words on Google's German Search Engine. Clearly, the responses will be in German but turning ON Google's Automatic Translation service is a great help. You'll need to install the Google Toolbar to access this tool.
2. CALCULATE THE BANK ANGLE YOURSELF - It is not difficult. Once you know the radius of a turn, the coefficient of friction between the tyres and the road surface and the approximate speed that will be used around that curve you can enter these into standard formulae to give you the banking angle for neutral steering. In other words the angle where the resultant centrifugal forces no longer tend to make the vehicle steer a wider or narrower course. This is the banking angle at which a driver can let go the steering wheel without the car careering up or down the bank. Once you have this angle, I would guess this would be the tangential angle at the centre of the track width. For example, the track will get steeper on the outside and shallower on the inside. Thus, the banking angle provides a range of 'neutral' steering angles to suit a range of car speeds. Here is a link to a PDF providing the basic formulae: Bank Angle Formulae
3. USE AN ON-LINE CALCULATOR - If this calculation method phases you, there is at least one ready-made on-line calculator where you can enter the variables and it comes up with the 'maximum' speed at any coefficient of friction and banking angle you input. It is here: Banked Circuit Speed Calculator. Enter the bend radius (in metres or feet); the static coefficient of friction between concrete and rubber (somewhere between 0.6 and 0.85 - I suggest using 0.75) and it calculates the speed. So if you know the speed at which you want to negoiate the curve, keep entering different bank angles until that speed results and then note down the Bank Angle. I imagine that the radius of the AVUS curve varies throughout the curve so you will need to measure the radius at regular intervals and input each radius to calculate the bank angle to allow the same vehicle speed at each interval. Hopefully this will result in a smooth change of bank angle for a given fixed speed.

Good luck.

Finally, I expect you've seen this but I was extremely surprised by what I found here about the AVUS and in particular, the method used to indicate its pure scale! AVUS Graphic

Edited by Sergio, 25 March 2013 - 18:49.

[R.W. Mackenzie]

You can drive AVUS and the Nordkurve today thanks to the people at Papyrus (now defunct) who created Grand Prix Legends and a fellow named Scott Przybylski who created a couple of versions of the AVUS circuit. They can be found here:

http://gpltd.bcsims....amp;send=Search

There are a few other versions by others available here:

http://gpltd.bcsims....amp;send=Search

Take a look here for some screen shots:

http://www.computerb...-3335793.html#6

Bob Mackenzie

[R.W. Mackenzie]

And here's a video showing a lap around in 1959 GP circuit but in what appears to be a 1967 Cooper-Maserati:



Don't know what all the bitching was about. Looks perfectly safe to me!

Bob Mackenzie

[LittleChris]

Looking at Google maps tonight, it appears that they have dug up the tarmac at the southcurve ( as used for the 1959 GP ) and started to do so on the North curve.