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View Full Version : Delta Wing would be un-racable, undrivable



e2mtt
5th September 2010, 05:02
Just thought I'd throw this out... all this talk about the Delta Wing, and the goofy looking prototype they built. There isn't any way you could race a Delta Wing in the real world (it might work in iRacing.com).

The front end would have virtually no downforce, and skinny tires. It would understeer like a truck. It would understeer even worse it it was running in the massive wake/tow of the huge butt-end of another Delta Wing car. If it slid wide (while understeering) & touched a wall with its massively wide tail end, the narrow little nose would snap sideways into the wall and wreck hard. No light "brush" of the wall possible.

I also think the extremely narrow front & wide rear would make it hard to judge the position of the car, causing a lot more accidental contact & wrecks. I can imagine brutal crashes if an overtaking car snagged on the wide tail, where the nose would snap sideways into the car being overtaken. I think you would end up with 2 cars barrel rolling down the track.

I hope they do build some prototypes. Maybe we should test it at 1/8 scale RC.

Jag_Warrior
5th September 2010, 06:04
From the time I first saw it (4 or 5 years ago?), I liked this. But my camp seemed to be pretty empty.

http://img149.imagevenue.com/loc151/th_59274_0Menards20Prototype20005_122_151lo.jpg (http://img149.imagevenue.com/img.php?image=59274_0Menards20Prototype20005_122_1 51lo.jpg)

BrentJackson
5th September 2010, 07:12
From the time I first saw it (4 or 5 years ago?), I liked this. But my camp seemed to be pretty empty.

http://img149.imagevenue.com/loc151/th_59274_0Menards20Prototype20005_122_151lo.jpg (http://img149.imagevenue.com/img.php?image=59274_0Menards20Prototype20005_122_1 51lo.jpg)

Hey, I liked that car in the past, and still do. :D

call_me_andrew
5th September 2010, 07:55
(it might work in iRacing.com)

Done and done.

http://www.youtube.com/watch?v=e2mqjL2P9O8

http://www.youtube.com/watch?v=4Cxe_hN5sDw

px400r
5th September 2010, 12:20
Just thought I'd throw this out... all this talk about the Delta Wing, and the goofy looking prototype they built. There isn't any way you could race a Delta Wing in the real world (it might work in iRacing.com).

The front end would have virtually no downforce, and skinny tires. It would understeer like a truck. It would understeer even worse it it was running in the massive wake/tow of the huge butt-end of another Delta Wing car. If it slid wide (while understeering) & touched a wall with its massively wide tail end, the narrow little nose would snap sideways into the wall and wreck hard. No light "brush" of the wall possible.

I also think the extremely narrow front & wide rear would make it hard to judge the position of the car, causing a lot more accidental contact & wrecks. I can imagine brutal crashes if an overtaking car snagged on the wide tail, where the nose would snap sideways into the car being overtaken. I think you would end up with 2 cars barrel rolling down the track.

I hope they do build some prototypes. Maybe we should test it at 1/8 scale RC.

Yeah, what does Bowbly know about designing race cars anyway...

garyshell
6th September 2010, 00:07
Yeah, what does Bowbly know about designing race cars anyway... :up:

My thoughts exactly. Here we have an armchair quarterback telling a professional car designer who spent a boatload of money on computer simulations that the design won't work. Priceless.

Gary

beachbum
6th September 2010, 02:51
:up:

My thoughts exactly. Here we have an armchair quarterback telling a professional car designer who spent a boatload of money on computer simulations that the design won't work. Priceless.

GaryA lot of well paid professional race car designers have built real stinkers in their time. Six wheel cars, "sidewinders", unusual weight bias, etc. The fact that no other professional designer has come up with any solution remotely similar to Bowby's suggests the other designers don't know what they are doing, Bolby has found some new mystery secret weapon, or there is some fundamental flaw in the premises that lead to the design. Until it is built and put on a track, it may be an impressive result of hundreds of hours of computer time, but it is still a computer simulation.

SarahFan
6th September 2010, 03:23
Honest question....

Has bowlby ever designed a car .... Or just enginered a few lolas a Reynard and the current dallara?

Marbles
6th September 2010, 03:48
After a long look at the Delta I really thought this would certainly set the league apart. It would be good and different and even people who don't know racing would do a double take. It would take the same skill to be fast. Small displacement, fuel sipping motors would make policing horse power an easy task.

If they allowed the same kit builder add on that they are currently proposing I would have been on board 100%.

When you think about how much open wheel cars changed in the decade from 1965 to 1975 do you think we could handle such a sea change 35 years later?

Chamoo
6th September 2010, 04:45
I think best case scenario for Randy Bernard, the Izod Indycar Series, Chip Ganassi, and Ben Bowlby would be to plan now for the Delta Wing to be the 2015 plan. I believe it was mentioned that this car cycle is for 3 years, and then they would be looking for a new car?

If they can get a Delta Wing on the track for 2012, they can test it for a year or two, get a whole bunch of them built and sold (if they work on track) and have them ready to become the new base of the 2015 Izod Indycar.

beachbum
6th September 2010, 12:47
When you think about how much open wheel cars changed in the decade from 1965 to 1975 do you think we could handle such a sea change 35 years later?What hasn't changed in 35 years is physics and air. The same basic forces experienced by a race car 35 or even 60 years ago have not changed. The levels have gone up dramatically, but basic engineering principles have not.

The Delta Wing does not violate any laws of physics or aerodynamics, but like every engineering exercise, certain parameters were set early in the design that dictate the direction of the exercise. It may eventually work beautifully, but it is so radical, there is no way to know how it will work on a track driven by real people. Any racing organization that is willing to gamble its future on unproven technology would be taking a HUGE risk, so prove the technology first (in real life) and then submit the ideas.

Actually, the changes of the 60's and 70's don't look so radical in hindsight. Many people suggest the biggest advances were tires and wings. Wider and stickier ties allowed different weight distributions to work (heavier rear bias was controllable) and aero increased overall grip and added the issue of aero balance. But some things didn't change much, such as that is how those forces are applied to the ground. Tracks were made wider to move the roll center further from the point of contact, then narrower for less drag until a balance was found. Wheelbases increased and decreased to impact the moment of inertia to make the car more stable or rotate better. Weight distributions have moved to the rear, then to the front (the Acura ARX-02a had 50-50 weight distribution and the same tires front and rear - very fifty-ish).

Yet in any given period, the solutions all ended up pretty similar. Some of that was dictated by regulations, but a lot was the result of engineering experience and knowledge leading to the same answers to the same questions. During the past 50 years of racing various radical solutions have been presented that looked "right", even from an engineering perspective. The original Mickey Thompson "roller skate" Indy Car, the Shadow Can-Am car, early ground effects cars. These all proved to be on the right track in many ways, yet were all basically failures in the earliest incarnations. The reasons were simple. They were such radical departures from convention (yet not as radical as the DW), that there were unknowns that bit them until the issues could be worked out over time.

The Delta wing may be a completely new answer, but NO ONE has shown it will work and especially, if the car dynamics will be something a driver can handle. Some of the premises have been tried many times before such as extreme rearward weight bias, down force basically only by undertray and rear wing, and odd tire sizes. In the past, cars where the driver sat well in front of the center of rotation (CG) proved to be very hard to drive. With aero by undertray, balancing downforce front to rear is difficult, which is why almost always wings and winglets sprout up. Odd size tires may work, but with a smaller contact patch, how will they wear?

Computers can simulate many of these factors, but the human computer is going to actually have to drive and ultimately race any such creation. Built a prototype and put in on the track and see how it works. The discussion and arguments will continue until a physical specimen is running on a track and compared back to back with current solutions.

I am evil Homer
6th September 2010, 14:42
Well here's two cars that worked perfectly in a wind tunnel and even at some test tracks:

http://www.youtube.com/watch?v=b31O4FmljGY

http://www.youtube.com/watch?v=qvSrCdgDeSM

Or how about an open wheel car designed purely with CFD - the current Virgin F1 car. Great success that's been...

px400r
6th September 2010, 15:07
A lot of well paid professional race car designers have built real stinkers in their time. Six wheel cars, "sidewinders", unusual weight bias, etc. The fact that no other professional designer has come up with any solution remotely similar to Bowby's suggests the other designers don't know what they are doing, Bolby has found some new mystery secret weapon, or there is some fundamental flaw in the premises that lead to the design. Until it is built and put on a track, it may be an impressive result of hundreds of hours of computer time, but it is still a computer simulation.

Back in those days, designers did not have access to powerful computers to do the simulations. It's much different today as computer processing power is cheap and more like commodities.

Getting back on point- unless people here care to post their CVs, they have no basis for dismissing Bowlby's design.

px400r
6th September 2010, 15:12
Honest question....

Has bowlby ever designed a car .... Or just enginered a few lolas a Reynard and the current dallara?

Bowlby was chief designer at Lola for 12 years. He wasn't just a "race engineer," he acutally led the design and development of Lola's champ cars during that period.

If there is anyone qualified to design a race car combining performance, manufacturing, and economics- it would be someone him- regardless of what armchair quarterbacks think of his work.

edv
6th September 2010, 15:52
A lot of well paid professional race car designers have built real stinkers in their time. Six wheel cars, ....

Despite the lack of tire development (and its 6 wheels) the Tyrell P34 achieved a race win, a pole position and fastest lap in 3 F1 races.

There's probably a lot of race cars that you would not call 'stinker' that performed far less than the P34.

anthonyvop
6th September 2010, 16:11
Despite the lack of tire development (and its 6 wheels) the Tyrell P34 achieved a race win, a pole position and fastest lap in 3 F1 races.

There's probably a lot of race cars that you would not call 'stinker' that performed far less than the P34.


Their drivers finished 3rd and 4th in the Championship and Tyrrell finshed 3rd in the Constructors.....Not too shabby.

e2mtt
6th September 2010, 16:19
:up:

My thoughts exactly. Here we have an armchair quarterback telling a professional car designer who spent a boatload of money on computer simulations that the design won't work. Priceless.

Gary

Yup. :-D I'm gonna keep sitting in my armchair & arrogantly declaring that it won't work, until they build some full size (or at least scale size actual models) prototypes & race them. I won't volunteer to be a test driver.

There are laws of physics regarding weight transfer & tire grip that dictate the all four corners of a car should have close to equal weight & tire grip distribution. The front tires take the majority of the load under braking and power-off steering. Tiny front wheels will tend to make for a car that doesn't stop or turn well (without power-on oversteer).

Putting the driver in a strange position in relation the center of gravity & overall vehicle envelope isn't impossible, just difficult & it will make it harder to learn. Suppose the Delta Wing is race-able, & doesn't snap sideways violently every time its rear fairing touches a wall... it will still require a very unique set of driving skills that don't translate.

Who would want a racing series running cars that race car drivers don't want to drive, and to master driving them you'd have to relearn most of your normal race-driving skills?

e2mtt
6th September 2010, 16:22
Regarding the Tyrell 6-wheeler... the 4 small front wheels were designed to provide similar grip as a 2 full size tires, in a more aerodynamic package. Quite the opposite of what the Delta Wing proposes.

Hoop-98
6th September 2010, 16:32
I have no lack of faith in Ben Bowlby's design and engineering capabilities but I find a number of things about the design hard to fathom.

I'll start with just one.

Weight is claimed to be 1030 with driver. With current driver weight allowances that implies a 850 pound race car.

We specified a cradle so we can run production based or GRE engines, but production 4s weigh from 270 to 400 pounds, the GRE is 240 pound minimum. Throw in a transaxle and clutch and you can't really have a 850 pound car.

I believe his weight projection is based on the MZR-R or similar which weighs 160 lbs.

Now that is a lot different than this can run any engine model we have been led to believe. I think as soon as you get closer to reality, the design will creep farther and farther away from the original design.

jm2c
rh

e2mtt
6th September 2010, 16:39
I have no lack of faith in Ben Bowlby's design and engineering capabilities but I find a number of things about the design hard to fathom.

I'll start with just one.

Weight is claimed to be 1030 with driver. With current driver weight allowances that implies a 850 pound race car.

We specified a cradle so we can run production based or GRE engines, but production 4s weigh from 270 to 400 pounds, the GRE is 240 pound minimum. Throw in a transaxle and clutch and you can't really have a 850 pound car.

I believe his weight projection is based on the MZR-R or similar which weighs 160 lbs.

Now that is a lot different than this can run any engine model we have been led to believe. I think as soon as you get closer to reality, the design will creep farther and farther away from the original design.

jm2c
rh

Wow. So basically they say they are going to build an entire carbon fiber structure that is both stiff enough to handle like a racecar & protect a driver in a high-speed crash, and it will only weigh about 500 lbs?

No way that will be cheap. :-)

I am evil Homer
6th September 2010, 16:51
I think the thing to remember it was always termed a "concept" - in that there may be engineering ideas you can take and evolve into a workable solution. But there's too many unknowns is the concept to really make an informed argument on whether it could be built, built cheaply enough or indeed work on a race track.

Oh and it's ugly as sin.

Hoop-98
6th September 2010, 16:52
Wow. So basically they say they are going to build an entire carbon fiber structure that is both stiff enough to handle like a racecar & protect a driver in a high-speed crash, and it will only weigh about 500 lbs?

No way that will be cheap. :-)

I think the current design is going to be about 650 for chassis minus engine/trans but including everything else.

Of course if we add 100 pounds of engine (160 up to 260) we have to add weight (and power) everywhere else.

Just about every "fresh" design gains weight and cost as reality of production approaches, but please , build one or we will forever think it was the Tucker conspiracy of racing.

rh

6th September 2010, 18:01
CRGE - They are a clean energy company with some serious alleged energy generation contracts.. should we buy at current level?


please also comment about it.

SoCalPVguy
6th September 2010, 18:10
I am a registered professional mechanical engineer and although my specialty is heat transfer, power generation, and HVAC- I just don't see how the DW will "Turn" given the narrow front track and very small tire contact patch versus the very large power-down contact patch in the rear on a much wider track.

Those guys make all the phone computer graphics they want showing the giant car zooming around but I won't believe it until I actually see it. Given that however I would rather ICS had "gone big" and picked a more radical concept than the rather generic model chosen.

maximilian
6th September 2010, 18:21
I still think the DeltaWing would be an exciting concept IFFFF they get rid of the ridiculous narrow front wheels. Regardless of whether they would be feasible from a steering/racing point of view, it just doesn't LOOK right to me. And looks ARE important.

Wouldn't most of you be able to live with this:
http://www.anasuya.com/delta.jpg

e2mtt
6th September 2010, 18:25
I still think the DeltaWing would be an exciting concept IFFFF they get rid of the ridiculous narrow front wheels. Regardless of whether they would be feasible from a steering/racing point of view, it just doesn't LOOK right to me. And looks ARE important.

Wouldn't most of you be able to live with this:
http://www.anasuya.com/delta.jpg

I'm sure it would be a lot more drivable on a road coarse... however without anything to generate downforce up front, it would still push like a truck.

Hoop-98
6th September 2010, 18:44
I am a registered professional mechanical engineer and although my specialty is heat transfer, power generation, and HVAC- I just don't see how the DW will "Turn" given the narrow front track and very small tire contact patch versus the very large power-down contact patch in the rear on a much wider track.

Those guys make all the phone computer graphics they want showing the giant car zooming around but I won't believe it until I actually see it. Given that however I would rather ICS had "gone big" and picked a more radical concept than the rather generic model chosen.

Computer controlled torque differential, and one would assume sense it has to turn under braking, similar braking differential. I think it was stated at the same point as not needing stagger.

rh

Hoop-98
7th September 2010, 10:59
Upon further review, the front to rear tire sizing somewhat approximates the weight distribution so it, according to it's designers, can turn on it's own self.

rh

electron
7th September 2010, 11:44
I have tried to forget about this ugly thing...

regarding the steering, if i remember correctly this was supposed to be the most radical idea of all (if memory doesn't fail me here)

This guy is NOT suppoed to steer with its front... well, some call it wheel -LOL, but with a newly created differential steering in the back!!!!

this was the point that eliminated all the "will neverr turn" discussions.
as aerdynamics might work, but making such a mechanical concept safe for racing (at highest speeds in an oval) costs masses of money - not speeking of the "test pilots" doing the rounds while the engineers figure it out.

you can't do such experiments with a field half full of rookies in general and all rookies to such a concept. with this, even a Franchitti becomes rookie again in terms of setup, behaviour in traffic and all technical stuff. Such a risk may not be ignored.

beachbum
7th September 2010, 12:05
And, what do you do if it doesn't work and you've mandated a whole series around it?The #1 issue with the whole concept. Bye Bye series.

chuck34
7th September 2010, 14:07
I have some experience with designing a car (Formula SAE). And I work in a field that has some to do with vehicle dynamics. No where near Bowlby's experience. But I do have at least some basics in the field. As I've said in other threads about this, I don't want to say it won't work. But it's gonna take a lot of convincing for me.

One point that really bugs me is the differential thing. Bowlby (and team) knows this thing won't turn on it's own, so they are relying on this electronic controlled diff thing. There are many electronic diffs in F1. They work ok. The problem is that F1 cars aren't reliant on them working all the time. If the controler fails in F1 (and they do), the car still drives, it's just not up to optimum. But if it fails on the DW, the thing won't turn. Bam! Understeer right into the wall at high speed. That doesn't give me a warm and fuzzy feeling.

Hoop-98
7th September 2010, 16:45
The Delta Wing people are adamant that the car will steer and rotate without assistance of the differential.

What is not clear is the arrangement of the front wheels. Are they independently sprung, where is the the roll center, is there a roll center etc....

Likely traditional front to rear roll stiffness equations will be changed. For all I know it may have them on 1 axle with a high trail design like a motorcycle.

Very odd how they are so forthcoming with some details and completely barren on others.

For example; if you double the downforce with the rear wicker, what happens to the center of pressure?

I am curious, for sure.
]
rh

chuck34
7th September 2010, 18:17
The Delta Wing people are adamant that the car will steer and rotate without assistance of the differential.

I find that very hard to believe.


What is not clear is the arrangement of the front wheels. Are they independently sprung, where is the the roll center, is there a roll center etc....

Hard to tell. I would assume that they would be independently sprung. But that's just an assumption.


Likely traditional front to rear roll stiffness equations will be changed. For all I know it may have them on 1 axle with a high trail design like a motorcycle.

That may very well be where this whole thing breaks down. All they've done is model this. Well the models do very well on cars that are known fairly well. And as with every model, there are assumptions. Those assumptions probably are not going to be correct for this thing.


Very odd how they are so forthcoming with some details and completely barren on others.

For example; if you double the downforce with the rear wicker, what happens to the center of pressure?

I am curious, for sure.
]
rh

It sure would be nice to see this thing on a track. It would answer a bunch of questions.

Hoop-98
7th September 2010, 18:42
From Deltawingracing

Key Specifications (estimated):
Weight with driver: 1,030 lbs. Horsepower: 300 BHP
Wheel base: 125 inches Aerodynamic drag: Cd 0.24
Front track: 24 inches Rear track: 70 inches (Center to center)

Key Technical features:

Engine and transmission are “non-stressed members” of the chassis structural design which allows
teams to install a wide variety of lightweight powertrains

The prototype will feature a 4 cylinder turbo charged engine that will produce approximately 300 horsepower at 7,000 rpm and weigh only 160 lbs fully dressed (Mazda MZR-R?)

Engine capacity, RPM and configuration freedoms are anticipated given only that the rate of fuel delivery to the engine will be controlled by a specially developed fuel flow rate control unit

Vehicle weight distribution is necessarily more rearward than traditionally seen with 72.5% of the mass on the larger rear tires

80% of the aerodynamic downforce acts on the rear of the car

Inline traction under acceleration through the rear tires is greatly enhanced by rearward weight and aerodynamic distributions

Unique amongst today’s racing cars 60% of braking force is generated behind the center of gravity giving a dynamically stable response

Locking propensity of the inside front wheel on corner entry is greatly reduced

Transmission features 6 speed oval and 5 speed plus reverse road track configurations with sequential paddle shift actuation

Differential features full torque vectoring active technology with driver control of gain for balance adjustment. “Active stagger” removes the expensive (expensive?) necessity for staggered rear tire diameters for ovals

Advanced computer modeling of structures, impact energy management, aerodynamics, vehicle dynamics and tires has been used to develop the virtual DeltaWing car

The car’s performance has been simulated on each configuration of race track encountered during the IZOD IndyCar Series Championship

Modern advanced materials and CNC construction techniques applied to achieve gains in light weight structures and occupant safety

Driver position, restraint layout and energy absorbency facility designed with the latest data on
survival criteria

Bold () from me.

methanolHuffer
7th September 2010, 22:26
If it ever was to be built and raced, it would receive incredible attention and hype...



... for about three weeks.

You see, cars can be exotic or cool or ugly or low-tech or revolutionary in design - if the racing is bland, if there is no real variety apart from the color - are fans going to follow it with the passion of when the days were good for the sport and you could actually see the differences in the cars and could hear the differences, too.

Even if the Delta Wing makes it, and who knows in these crazy times, it might be too boring to watch a 500 mile race.

If I'm wrong I'll volunteer to paint one up to match my John Deere.

Hoop-98
8th September 2010, 01:38
I have been doing research on this topic and I think the secret may be the narrow track.

It's possible we are rotating on more of a camber thrust model than the traditional slip angle induced yaw.

I think this will help illustrate the concept..

http://www.atnet.it/lista/dav1.gif

garyshell
8th September 2010, 03:30
I have been doing research on this topic and I think the secret may be the narrow track.

It's possible we are rotating on more of a camber thrust model than the traditional slip angle induced yaw.

I think this will help illustrate the concept..



Well Hoop, there you go talking sense and reason again, replete with actual data to back it up. Oh psshaw!

Gary

FormerFF
8th September 2010, 03:33
I'm with beachbum on this one. Racing designers have good models for conventional cars. When you make a radical change, the models quite often break down. Extraordinary claims require extraordinary proof.

That weight is a little suspicious as well. Like Starter pointed out, that's less than a Formula Ford. Granted an FF is a steel spaceframe, but the bare FF chassis doesn't weigh all that much, it's all the other pieces. And that's a car that pulls less than 2 Gs and only goes 125 mph.

In any case, the onus is on DeltaWing to prove that the car works. They'd need to build half a dozen of them and track test them in a group.

Is there any reason to believe that this is what the prospective fanbase is looking for?

anthonyvop
8th September 2010, 03:58
http://www.racingnation.com/images/column_photos/100210DeltaWingCar.jpg

A few questions.

#1 How would the front wheels turn without rubbing against the inside bodywork?

#2 How were they going to cool the engine with such tiny and ill positioned radiator intakes? If you look at their own airflow photos it shows the location being a low pressure area. http://deltawingracing.com/2010/02/airflow-image-gallery/

#3 How are the brakes to be cooled?

#4 Where would the engine intake be?


http://www.carbonfiberguru.com/wp-content/uploads/2010/02/2012-delta-wing-indycar2-300x199.jpg
#5 With the flat, almost perpendicular rear end wouldn't that create lots of turbulence for any car following?

Hoop-98
8th September 2010, 04:05
http://www.racingnation.com/images/column_photos/100210DeltaWingCar.jpg

A few questions.

#1 How would the front wheels turn without rubbing against the inside bodywork?

#2 How were they going to cool the engine with such tiny and ill positioned radiator intakes? If you look at their own airflow photos it shows the location being a low pressure area. http://deltawingracing.com/2010/02/airflow-image-gallery/

I am not an advocate for this design study, but I think tiny and ill positioned are dimensionless criticisms without validation.

#3 How are the brakes to be cooled?

#4 Where would the engine intake be?


http://www.carbonfiberguru.com/wp-content/uploads/2010/02/2012-delta-wing-indycar2-300x199.jpg
#5 With the flat, almost perpendicular rear end wouldn't that create lots of turbulence for any car following?

This supposedly explains all.

http://i54.tinypic.com/2iw4z15.jpg

rh

e2mtt
8th September 2010, 04:49
I have been doing research on this topic and I think the secret may be the narrow track.

It's possible we are rotating on more of a camber thrust model than the traditional slip angle induced yaw.

I think this will help illustrate the concept..



I wondered about this... I did notice that the front tires looked rounded like motorcycle tires in the picture that anthonyvop posted. This might make it a little better getting around a road/street course... probably still not great.
I don't think this helps at all on an oval, where the overall shape is going to make passing harder & wall contact MUCH more dangerous.

beachbum
8th September 2010, 12:06
This supposedly explains all.

http://i54.tinypic.com/2iw4z15.jpg

rhI have seen that design before! - yard darts

electron
8th September 2010, 12:25
http://www.racingnation.com/images/column_photos/100210DeltaWingCar.jpg

A few questions.

#1 How would the front wheels turn without rubbing against the inside bodywork?

#2 How were they going to cool the engine with such tiny and ill positioned radiator intakes? If you look at their own airflow photos it shows the location being a low pressure area. http://deltawingracing.com/2010/02/airflow-image-gallery/

#3 How are the brakes to be cooled?

#4 Where would the engine intake be?


http://www.carbonfiberguru.com/wp-content/uploads/2010/02/2012-delta-wing-indycar2-300x199.jpg
#5 With the flat, almost perpendicular rear end wouldn't that create lots of turbulence for any car following?


My answers:
#1 most likely NOT AT ALL, since steering is done by the rear differential only! no conventional steering as part of the concept.

#2 would seem so at first glance, but if the graphics don't ly it is actually the best possible place for the intake.
another proof where common engineering giuesswork conflicts with calculations. aero simulation like this is pretty reliable these days.

#3 , 4, 5: we know nothing about the flow below the car or if they intend on taking air in from there. doesn't seem so though
actually I do believe that this rendering does not fully adress such details yet.

a custom 300HP engine does not require such excessive cooling and air intake though as the current OW engines do. As a lighteweight car brakes will also not be as much stressed, so also less cooling needed in general terms.
might actually be done through the same air intakes on the side.

Easy Drifter
8th September 2010, 14:25
As long a IC were going with basically a spec tub or car there is no way anything that radical could have been chosen. If it didn't work the whole series would be toast or have to go back to the current cars.
Even if it works it is going to take quite a bit of development and I suspect be very tricky to drive.
Differential steering or any type of full rear steering is very tricky as anyone who has tried to back a car up fast will attest to.
The only way I could see it being allowed would be if the series was thrown wide open regarding design with multiple chassis.
Without actually seeing more I could also see a possible problem with crush structure around the driver from side impacts.
I am not saying it won't work but I can see why the League could not choose it.

Mark in Oshawa
8th September 2010, 18:25
Well, after reading 3 pages of posts on this subject, I am with Hoop...a skeptic...but still curious to see this beast hit the track.

The thing's one must remember are this:

Chip isn't spending this much money on a pipe dream that he doesn't believe wont work, and Chip's record in racing is arguably better than anyone's this year. Chip doesn't waste his money....and he hasn't stopped development on this concept. What does that tell you? He believes...and he has built more race cars than any of us lot.

The second thing that I get out of this is that Bowlby is a radical thinker. We need more of those in racing....and his track record would also indicate he knows more about race cars than any of us also.

That said, the educated skeptic's such as Hoop, Starter and others say they don't get how it works also hold water, but I am going to just point out when Chip is spending his own money on this, I have to say I want to see it turn laps before I am judging this effort. The technology here is off the charts and we wont need 4 or 6 cars on the track to prove it, if it turns laps anywhere close to the Dallara of today, the concept is more than half way to being proven...

Hoop-98
8th September 2010, 20:03
I want to restate, that to the extent of my research on this topic, the Delta Wing car steers with the front wheels, not with the differential.

Reviewing the information linked on their website makes this point clearly.

The variable torque split feature is to allow oval operation without the need for stagger.

When you look at the weight distribution the tire sizes are in fact proportional to the load carried.

What I cannot determine is the caster/trail of the front axle, front steering angles, ackermann, etc..

The displayed model makes it difficult to envision the steering angles, but nothing specifically precludes the front wheels from steering.

Open wheeled cars are inherently inefficient, what this car does is basically create a open wheeled car in name, but not in the typical understanding of open wheel fans. Might as well cover the wheels entirely and pick up a couple more points of drag reduction.

The car weight likely depends on a purpose built racing engine (160 lbs) if a GRE us used that will add 80 pounds of engine weight plus all the weigt needed to accommodate the bigger heavier engine.

The Power to weight 3.4 lbs per HP, compares to the proposed 2012 car which will be around 2.3 meaning that it's low speed acceleration will be more like an Indy Light.

This would make street circuit performance less than desirable in my opinion.

But, by all means build it and show us what it can do.

rh

chuck34
8th September 2010, 20:40
I want to restate, that to the extent of my research on this topic, the Delta Wing car steers with the front wheels, not with the differential.

Reviewing the information linked on their website makes this point clearly.

The variable torque split feature is to allow oval operation without the need for stagger.

When you look at the weight distribution the tire sizes are in fact proportional to the load carried.

What I cannot determine is the caster/trail of the front axle, front steering angles, ackermann, etc..

The displayed model makes it difficult to envision the steering angles, but nothing specifically precludes the front wheels from steering.

Open wheeled cars are inherently inefficient, what this car does is basically create a open wheeled car in name, but not in the typical understanding of open wheel fans. Might as well cover the wheels entirely and pick up a couple more points of drag reduction.

The car weight likely depends on a purpose built racing engine (160 lbs) if a GRE us used that will add 80 pounds of engine weight plus all the weigt needed to accommodate the bigger heavier engine.

The Power to weight 3.4 lbs per HP, compares to the proposed 2012 car which will be around 2.3 meaning that it's low speed acceleration will be more like an Indy Light.

This would make street circuit performance less than desirable in my opinion.

But, by all means build it and show us what it can do.

rh

If the diff is only there for "stagger" then it seems to me to be worse than I thought. Look at a dragster, it also has weight to tire size that are proportional, does it turn? Sure that's a bit more extream than the DW, but the concept seems the same.

Again, like the rest of you I want to see the thing run. But I' very sckeptical

e2mtt
8th September 2010, 21:58
New "formula" series get created all the time. If all these investors (some of whom are very successful in other racing endeavorers) are so convinced of the Delta Wing, they need to get some built, find some backers who like the high tech, new look, etc., and start a new feeder/support series. There are probably lots of race tracks that would be happy to add a high profile support series to a race weekend.

They need to put up, or shut up.

I guarantee I will watch the race!

anthonyvop
8th September 2010, 21:59
I have seen that design before! - yard darts

What you have is a top and bottom view. Both of which show less than what would be called optimum air pressure.

Side views show even less. Not to mention the small inlets.

FormerFF
9th September 2010, 03:13
The Delta Wing reminds me of an LSR car:
http://upload.wikimedia.org/wikipedia/commons/e/ec/Goodwood2007-121_The_Blue_Flame.jpg

If the goal of all this is efficient top speed, I have no doubt that the Delta Wing's a winner. But the goal is to put on exciting racing that interests fans. That, not so much.

I could be totally wrong. But there's nothing to indicate that this will work. Bring on the prototypes and let's see them on the track.

Hoop-98
9th September 2010, 03:49
Starter "How will this translate to weight transfer to the front, under braking, while turning into a corner? A big question in my mind."

try this on for size :)


Simple weight transfer calculations for 1.5G Left turn, 1.5G Braking, 1.5G Combined

Assumptions:
Weight with driver: 1,030 lbs.[/*:m:34qvax8q]
Wheel base: 125 inches[/*:m:34qvax8q]
Front track: 24 inches[/*:m:34qvax8q]
Rear track: 70 inches[/*:m:34qvax8q]
Rear weight 72.5%[/*:m:34qvax8q]
Front VCGh 13"[/*:m:34qvax8q]
rear VCGh 17"[/*:m:34qvax8q]No Aero, no weight jacking from caster, SAI.

http://i52.tinypic.com/jgjzg1.jpg

Hoop-98
9th September 2010, 05:05
Understanding Camber Thrust vs Slip Angle Cornering forces (a possible application to the narrow front track Delta Wing)

On bicycles and motorcycles, camber thrust contributes to the centripetal force necessary to cause the vehicle to deviate from a straight path, along with cornering force due to the slip angle, it can be the largest contributor,and in some cases is the sole contributor. Camber thrust contributes to the ability of bikes to negotiate a turn with the same radius as automobiles but with a smaller steering angle. When a bike is steered and leaned in the same direction, the camber angle of the front tire is greater than that of the rear and so can generate more camber thrust, all else being equal.


rh

nigelred5
9th September 2010, 12:56
I can't get to it here at work, however a fellow member of a discussion group I
m a member of has a three wheel vehicle of his own construction that uses camber thrust steering. The 2 front wheels do not steer at all in the traditional sense. All stering is through changing camber. I'll try to pull up his design and videos of hte vehicle in action. Granted it is a leaning three wheel vehicle, however the steering concept would appear very similar to what Hoop described.

garyshell
9th September 2010, 16:53
Just a question for thought. When Chip and the other folks funding this saw the first preliminary designs, don't you think the first thing they asked was the same question being posed here: "How will this thing steer?". And if there wasn't a sufficient answer to that question, do you REALLY think the design would have ever gone ANY further than that?

Yes, we have no idea how it will steer and we would all like to see it on track, but I just think its funny watching all the experts here tell us how it is not possible for it to ever work. I am in total wait and see mode, but not doubting the design is at least plausible.

Gary

Hoop-98
9th September 2010, 17:07
Just a question for thought. When Chip and the other folks funding this saw the first preliminary designs, don't you think the first thing they asked was the same question being posed here: "How will this thing steer?". And if there wasn't a sufficient answer to that question, do you REALLY think the design would have ever gone ANY further than that?

Yes, we have no idea how it will steer and we would all like to see it on track, but I just think its funny watching all the experts here tell us how it is not possible for it to ever work. I am in total wait and see mode, but not doubting the design is at least plausible.

Gary

I agree Gary, I am just "guessing" at some approaches as far as steering goes. I am pretty sure they know it will go around hairpins, pull in and out of the pits etc.

I have more doubt about some of it's stated 'advantages" than I do it's cornering.

rh

beachbum
9th September 2010, 18:32
On street and racing bikes. yes, they're pretty well balanced. The closest motorcycle equivalent to the Delta Wing, in weight distribution terms, would be a chopper, or maybe a trike. They don't corner nearly as well.Motorcycles in general don't corner nearly as well as a car just be cause of contact patch size. The tire contact patch is pretty small, although much larger than it may appear because of deflection. Still, not nearly as much as a car race tire.

What is particularly interesting to me is the current trend to more weight on the front end or race vehicles. The Acura ALMS P1 car was almost 50-50. The idea (which worked) was to spread the loads move evenly over all of the tires so they all contributed. Even racing motorcycles have been moving weight forward to turn better. While the rearward weight bias of the DW will likely work, the question becomes "how well?" and for how long. It is asking a lot for the rear tires to be providing a significant portion of side loads and all of the acceleration.

FormerFF
10th September 2010, 04:01
Motorcycles in general don't corner nearly as well as a car just be cause of contact patch size. The tire contact patch is pretty small, although much larger than it may appear because of deflection. Still, not nearly as much as a car race tire.

What is particularly interesting to me is the current trend to more weight on the front end or race vehicles. The Acura ALMS P1 car was almost 50-50. The idea (which worked) was to spread the loads move evenly over all of the tires so they all contributed. Even racing motorcycles have been moving weight forward to turn better. While the rearward weight bias of the DW will likely work, the question becomes "how well?" and for how long. It is asking a lot for the rear tires to be providing a significant portion of side loads and all of the acceleration.


Then there's the other obvious question - how do you get it stopped with those small front tires and limited front downforce? Certainly the severe rearward weight bias will help get some braking and at higher speeds downforce will help keep the rears stuck to the pavement, but at lower speeds it's all mechanical grip, and I just don't see those skinny fronts generating all that much stoppage.

Hoop-98
10th September 2010, 04:14
Then there's the other obvious question - how do you get it stopped with those small front tires and limited front downforce? Certainly the severe rearward weight bias will help get some braking and at higher speeds downforce will help keep the rears stuck to the pavement, but at lower speeds it's all mechanical grip, and I just don't see those skinny fronts generating all that much stoppage.

At the risk of sounding like an advocate, which I am not.

The front tires are about 41% the size of the rears and in a 1.5G decel without aero would be carrying about 42 % of the load.

rh

Mark in Oshawa
10th September 2010, 08:11
All your numbers Hoop say to me this wont work, but as we all have said, we want to see Bowlby's beast on a race track.

I think he has oversold this concept....

Your stats, explanations and the like give me the justification for saying I don't think it can work and I knew all of what you explained more or less just by looking at it. As it once was said, if it looks right, it is right....and this doesn't look right.

All that and a quarter wont buy coffee if this car turns out a pit lane in the next year and proves us all wrong. Brilliant ideas often are dismissed by well meaning and intelligent skeptics all the time....and yet they win out in the end. Is this a dead end or a brilliant idea? Time will tell..as long as Chip is writing the checks. I want to be a fly on the wall in that conversation...

chuck34
10th September 2010, 14:49
At the risk of sounding like an advocate, which I am not.

The front tires are about 41% the size of the rears and in a 1.5G decel without aero would be carrying about 42 % of the load.

rh

Yes, but those numbers tell us nothing about what slip angle the tires are at. Or if they are using camber thrust, what camber angle. We need those numbers along withe the force and moment data for the tires to know if the can create enough force to turn the darn thing. And to my minorly educated eye, I don't see it

Hoop-98
10th September 2010, 17:04
I am sure Ben Bowlby and his team know orders of magnitude more about this than "we" do. I believe it can/will negotiate tracks at a respectable rate of speed.

I do not think it will be a successful car in the open wheel market because, despite the tops of the tires being exposed , it's no more of an open wheel car (IMO) than a LMP.

I would also bet the prototype ends up heavier, more powerful etc...

The Atlantic P/W ratio doesn't inspire great thoughts on street courses, again, IMO.


jm2c
rh

SarahFan
10th September 2010, 17:38
I would also bet the prototype ends up heavier, more powerful etc...


rh


and i would add more expensive......

chuck34
11th September 2010, 01:06
I am sure Ben Bowlby and his team know orders of magnitude more about this than "we" do. I believe it can/will negotiate tracks at a respectable rate of speed.

I do not think it will be a successful car in the open wheel market because, despite the tops of the tires being exposed , it's no more of an open wheel car (IMO) than a LMP.

I would also bet the prototype ends up heavier, more powerful etc...

The Atlantic P/W ratio doesn't inspire great thoughts on street courses, again, IMO.


jm2c
rh

Why does Bowlby necessarily know orders of magnitude more than we do? Sure he probably does. But that does not mean he can't be mistaken, or believe so much in his computer models that he can't see it's flaws. It happens all the time. This thing just doe not pass the "smell test". I want to see it, I want to be proven wrong, I really do. But it's going to take a lot to convince me. Camber thrust just doesn't seem to provide the cornering force needed. Look up the camber car some time. It's a car that tried to use camber thrust to corner, just like you are suggesting. This was tried in the 60's, and abandoned. Tells me it didn't work out too well.

I'm on the road right now, but I have a couple of ways to maybe model some of this stuff, and I'll try to really dig into it when I get home.

Again, I don't want to completely dissmiss this idea, but it just doesn't add up to me at this point

maximilian
11th September 2010, 01:11
Whether it "works" or not, to me the narrow front just looks ridiculous and too far removed from what an "open wheel race car" *should* look like (I have no problem with the rest, just that narrow front, mind you), and that makes the entire project a non-starter to me.

FormerFF
11th September 2010, 03:27
Whether it "works" or not, to me the narrow front just looks ridiculous and too far removed from what an "open wheel race car" *should* look like (I have no problem with the rest, just that narrow front, mind you), and that makes the entire project a non-starter to me.

If the appearance of the car is off-putting to race fans, then it doesn't matter if it is technically successful. If people don't turn out to watch it race, it is a failure.

garyshell
11th September 2010, 05:49
Look up the camber car some time. It's a car that tried to use camber thrust to corner, just like you are suggesting.

You mean this car? We had it at our show back in 2004. Very interesting piece.

There is an interesting article here: http://www.telegraph.co.uk/motoring/4757537/Camber-control-ahead-of-its-time.html
The car spent a period of time at a local restoration garage owned by Dean Butler who is mentioned in the article. I got to spend some time looking at it at Dean's garage. I am not so sure the Milliken MX-1 was a "failure". It was a private test bed for Bill's ideas, but as the article says he never published his findings. I don't know what the F400 is that the article says used "similar principles".

Gary

http://www.ohioconcours.com/gallery04/R/images/IMG_3381.jpg

garyshell
11th September 2010, 06:08
More about Milliken's car:



This windfall helped revive a radical prototype that Milliken built in the early 1960s. Colleague Al Fonda's 1956 IME paper had revealed the powerful cornering forces that steeply cambered tires generated-banked tires like those of motorcycles. While Fonda built a banking-wheel test vehicle to experiment with this in the real world, Milliken started fabricating a tube-framed mid-engined single-seater with its wheels fixed in banked positions-splayed outward at both sides. "With his high-camber car he kind of invented around me," Fonda recalled. "I knew what I was doing, but not what he was doing. He was taking my enthusiasm for the high camber force of the tilted wheel and making use of it in a different way."

Completed in 1967, Bill's MX-1 "Camber Car" is powered by an 80-horsepower two-stroke driving its rear wheels. After tests and evaluations it was put in storage around 1980, only to be resurrected in the 21st Century thanks to the enthusiasm of Jim Himmelbach and Dean Butler. It was restored and entered by Butler for Bill to drive in Goodwood's 2002 Festival of Speed. After its appearance on Goodwood's hill, where it wowed the knowledgeable spectators, Bill and Butler took the red MX-1 to a proving ground where they could probe its limits.

"The secret of it is that when you go round a corner, pretty soon you've got no load on the inside wheels to speak of so it's all on the outside wheels," Milliken explained. "It turns out that the camber thrust-which is helping you-is directly proportional to the load. This to me is astounding. The more load you transfer, the more that tire wants to stick. You don't have to get the center of gravity low; in fact the more weight transfer there is the better it likes it. It likes load transfer. We set it up so it's neutral steer at the limit. We adjusted the brake distribution so that it just brakes a tiny bit first on the front so you can't spin it. The car itself doesn't want to spin. At Goodwood the car was one helluva lot better than the driver. I kept going into the turns faster than I felt comfortable, and it just went around! I never had the time or the guts to go in as hard as I'm sure the car would have done."

A high-speed automobile that probes the limits of vehicle handling and cornering in a revolutionary way-what could better exemplify the extraordinary career of Bill Milliken? Somehow he's beaten the Devil to continue to contribute to our automotive and aviation knowledge. And he's having a lot of fun doing it!


Full article here:
http://www.bentleypublishers.com/ludvigsen/aq-milliken-biography.htm

If you have the time, the lengthy article is a VERY good read.

Gary

Hoop-98
11th September 2010, 16:17
I suggest;

Equations of Motion - Adventure, Risk and Innovation. An Engineering Autobiography by William F. Milliken,


Very full life...

rh

chuck34
12th September 2010, 19:02
Gary the reason I call the camber car a failure is because nothing came of it. So many of Millikin's ideas and concepts were used, that sine this one wasn't, it raises questions of it's usefulness. But maybe it's just one of those things that had potential, but never exploited. And looking at everything I've seen about the DW, I don't think it will be using anything as extream as this car. Certainly not in static camber. And to get that amount of dynamic camber, they would have to be using some really exotic suspension geometry that I've never seen or heard of before.

Hoop, I haven't read his autobiography, but Racecar Vehicle Dynamics is pretty much THE textbook on the subject. See my sig ;)

Hoop-98
12th September 2010, 19:34
Gary the reason I call the camber car a failure is because nothing came of it. So many of Millikin's ideas and concepts were used, that sine this one wasn't, it raises questions of it's usefulness. But maybe it's just one of those things that had potential, but never exploited. And looking at everything I've seen about the DW, I don't think it will be using anything as extream as this car. Certainly not in static camber. And to get that amount of dynamic camber, they would have to be using some really exotic suspension geometry that I've never seen or heard of before.

Hoop, I haven't read his autobiography, but Racecar Vehicle Dynamics is pretty much THE textbook on the subject. See my sig ;)

It's on my coffee table!

garyshell
13th September 2010, 03:41
But maybe it's just one of those things that had potential, but never exploited.

I do think that is the key. Don't know if you read the long article I linked to above, but it talks about Miliken and Dean taking the car to a test track AFTER the Goodwood appearance to see what it was really capable of. This goes a long way to showing that Miliken himself never really did much with the car after his first experimentation with it. He never even published any of his early findings.

Gary

chuck34
13th September 2010, 16:36
I do think that is the key. Don't know if you read the long article I linked to above, but it talks about Miliken and Dean taking the car to a test track AFTER the Goodwood appearance to see what it was really capable of. This goes a long way to showing that Miliken himself never really did much with the car after his first experimentation with it. He never even published any of his early findings.

Gary

Even if that car did/does have potential, and apparently it does the DW concept can't get the kind of extreems in camber angle that this car has, or a motor cycle has. Perhaps some sort of "camber tire" could be developed, but I don't think so. The more I've thought about it, the less I think camber thrust is the key to making this thing drive.

beachbum
13th September 2010, 17:00
Even if that car did/does have potential, and apparently it does the DW concept can't get the kind of extreems in camber angle that this car has, or a motor cycle has. Perhaps some sort of "camber tire" could be developed, but I don't think so. The more I've thought about it, the less I think camber thrust is the key to making this thing drive.The car in the pictures is running motorcycle tires. They are designed to run at extreme angles where camber thrust is significant, particularly in wide tires. But the contact patch is still very small compared to a wide car tire, so the actual forces that can be transmitted to the road are smaller as well.

chuck34
13th September 2010, 18:36
The car in the pictures is running motorcycle tires. They are designed to run at extreme angles where camber thrust is significant, particularly in wide tires. But the contact patch is still very small compared to a wide car tire, so the actual forces that can be transmitted to the road are smaller as well.

Yes and the tires I've seen on the DW are about the same size as a motorcycle tire.

As a point of reference, one tire that I'm fairly familiar with (about the size of a current IndyCar front tire) generates about 25lbs of "extra" lateral force for every degree of camber at 500lbs vertical load and peak slip. Granted this is not a motorcycle tire, nor was it designed to use camber thrust for corner force generation. That added force isn't really too significant. The camber thrust does go up as you increase the vertical load, but, as we've all seen, there isn't much vertical load on the DW's front tires.

The point is that in order to generate significant amounts of camber thrust, you have to run extreme camber angles. I don't see how the DW can do this. Now they may have some very exotic suspension geometry, or new type of tire that would make this work. But that doesn't really give me any confidence with the raceability of the thing.

veeten
13th September 2010, 19:17
The Delta Wing reminds me of an LSR car:
http://upload.wikimedia.org/wikipedia/commons/e/ec/Goodwood2007-121_The_Blue_Flame.jpg

Actually, I believe you mean something like this...
http://www.myrideisme.com/Blog/wp-content/uploads/2010/06/Spirit-of-America-Land-Speed-Racer.JPG

Looking at the steering layout, it would have to be in some ways like the Tomahawk motorcycle that DaimlerChrysler developed back in the late 90's, where the wheels tilt to go into a turn.

chuck34
14th September 2010, 18:47
OK, I've done some work with this using CarSim. Granted there are a huge number of unknowns/assumptions that I've made. Basically there is a pre-loaded F3 car in the program, so I've modified from there. I kept the engine and aero maps the same from the F3, and modified the suspensions. The wheelbases, and track widths should be right. The kinematics I've kept the same from the F3 car with the exception that I gave the DW a lot more camber gain in the front (3x). The tires from the F3 car were used for everything except the DW front. For that I used 41% of the lateral capability, and 3x the camber thrust.

I then ran two tests. The first was basically a J turn. The car goes 80kph and turns the steering wheel to 57 degrees and holds it there. The IndyCar makes a turn radius of 70 meters. The DW a radius of 150 meters.

The next test is a 500ft radius constant turn with increasing throttle. The car starts from a standstill and gradually adds throttle, at the end of the test both cars are going 120kph. The steering angle of the IndyCar at the end is about 10 degrees with a path deviation of less than a quarter meter. The DW has a steering angle of 35 degrees and a path deviation of over 2 meters.

What does all this mean? Well not much really, except that to me it still looks like this thing will have big understeer issues. Look out at Long Beach :) The problem is that I have made a whole bunch of assumptions, and we all know what those can do to you ;)

Anyway that's how I see it, for what that's worth.

Hoop-98
15th September 2010, 02:28
Chuck, I am pretty sure these guys (DeltaWing) have modeled this car and it can perform basic turns to a comparable degree of the Dallara.

Exactly how they achieve this is unknown, but within the realms of possibility.

BTW, for those wondering about race car setup, I found a good manual designed for a Dallara Formula 3 car, plenty of great info.

http://www.dallara398.com/library/f398manual.pdf

rh

chuck34
15th September 2010, 15:07
Chuck, I am pretty sure these guys (DeltaWing) have modeled this car and it can perform basic turns to a comparable degree of the Dallara.

Exactly how they achieve this is unknown, but within the realms of possibility.

BTW, for those wondering about race car setup, I found a good manual designed for a Dallara Formula 3 car, plenty of great info.

http://www.dallara398.com/library/f398manual.pdf

rh

Yes I'm sure they did. And I don't think that it would be quite as bad as I have modeled it. On the other hand, every fiber of my being says that this thing is going to understeer like a pig. Every car that I know of for the past 50 years or so has a front track slightly wider than the rear track. That doesn't just "happen". There are reasons for it. Now this group is trying to tell us that a car with this type of set-up will go around the hairpin at Long Beach with no problem?

Extraordinary claims require extraordinary proof. And as the details seem to be a bit sparse at this point, I'm very skeptical of it.

I still want to see the thing built and run. I think ALL of us can/will learn a lot from it.

Hoop-98
16th September 2010, 01:02
Yes I'm sure they did. And I don't think that it would be quite as bad as I have modeled it. On the other hand, every fiber of my being says that this thing is going to understeer like a pig. Every car that I know of for the past 50 years or so has a front track slightly wider than the rear track. That doesn't just "happen". There are reasons for it. Now this group is trying to tell us that a car with this type of set-up will go around the hairpin at Long Beach with no problem?

Extraordinary claims require extraordinary proof. And as the details seem to be a bit sparse at this point, I'm very skeptical of it.

I still want to see the thing built and run. I think ALL of us can/will learn a lot from it.

Without any info on the front steering we are just wildly guessing. Most 4 wheel cars understeer behavior is to a large degree controlled by the ratios of front and rear roll stiffness. see the Corvair stuff in Millikens book.

This car appears to follow the 3 wheeler models more than four wheelers but again, all a guess.

rh

nanders
16th September 2010, 02:57
Chuck, I am pretty sure these guys (DeltaWing) have modeled this car and it can perform basic turns to a comparable degree of the Dallara.

Exactly how they achieve this is unknown, but within the realms of possibility.



They used rFactor Pro simulator where they can plugin their own wind tunnel and mechanical parameters. http://www.rfactor-pro.com/ It says it will race. I saw the simulation. I'm sure you did too.

beachbum
16th September 2010, 04:07
They used rFactor Pro simulator where they can plugin their own wind tunnel and mechanical parameters. http://www.rfactor-pro.com/ It says it will race. I saw the simulation. I'm sure you did too.I may have seen a simulation, but I haven't seen actual hardware with an actual driver on an actual track.

Unless something changed recently, Indy car doesn't race computers.

nanders
16th September 2010, 04:16
I may have seen a simulation, but I haven't seen actual hardware with an actual driver on an actual track.

Unless something changed recently, Indy car doesn't race computers.

Yes they do. Everyday. And things are learned.

beachbum
16th September 2010, 12:26
Yes they do. Everyday. And things are learned.Sure teams run sophisticated simulations all the time. But there are no fans watching, no trophies given out, no TV package. That happens when hardware hits the track.

As computer programmer and graduate mechanical engineer, I understand the limits of all simulations. If the parameters and algorithms being used are based on known factors and have been validated against known results, they can be extremely close to reality. But as the values move further from proven relationships the error window widens. Nothing like the DW has been built to validate the computer results and assumptions. The CFD is undoubtedly accurate, but I am suspicious of the chassis dynamic simulations. There seem to a few vague aspects, like how torque vectoring will be created and controlled. The other unanswered question is how will it drive, especially in traffic?

Build it, drive it, validate the simulation, and then publish the results. Until then, it remains nothing more than a video game.

nanders
16th September 2010, 14:03
I think you are going to get your wish.


Sure teams run sophisticated simulations all the time. But there are no fans watching, no trophies given out, no TV package. That happens when hardware hits the track.

As computer programmer and graduate mechanical engineer, I understand the limits of all simulations. If the parameters and algorithms being used are based on known factors and have been validated against known results, they can be extremely close to reality. But as the values move further from proven relationships the error window widens. Nothing like the DW has been built to validate the computer results and assumptions. The CFD is undoubtedly accurate, but I am suspicious of the chassis dynamic simulations. There seem to a few vague aspects, like how torque vectoring will be created and controlled. The other unanswered question is how will it drive, especially in traffic?

Build it, drive it, validate the simulation, and then publish the results. Until then, it remains nothing more than a video game.

chuck34
16th September 2010, 14:14
Without any info on the front steering we are just wildly guessing. Most 4 wheel cars understeer behavior is to a large degree controlled by the ratios of front and rear roll stiffness. see the Corvair stuff in Millikens book.

This car appears to follow the 3 wheeler models more than four wheelers but again, all a guess.

rh

True, and I wanted to play around with roll stiffnesses and other things, but I haven't really had a chance to just yet. Maybe in the next few days I'll be able to look at it again.

As for the wild guessing ... Yep that's all we are doing, and that is what gives me a bit of an uneasy feeling. If something so radical is to be accepted as a spec car, I really feel that more explaination is in order so that all of us die-hards with a small bit of mechanical know-how (you know the only fan base left, just about) would have a bit more buy-in with this car.

chuck34
16th September 2010, 14:14
Sure teams run sophisticated simulations all the time. But there are no fans watching, no trophies given out, no TV package. That happens when hardware hits the track.

As computer programmer and graduate mechanical engineer, I understand the limits of all simulations. If the parameters and algorithms being used are based on known factors and have been validated against known results, they can be extremely close to reality. But as the values move further from proven relationships the error window widens. Nothing like the DW has been built to validate the computer results and assumptions. The CFD is undoubtedly accurate, but I am suspicious of the chassis dynamic simulations. There seem to a few vague aspects, like how torque vectoring will be created and controlled. The other unanswered question is how will it drive, especially in traffic?

Build it, drive it, validate the simulation, and then publish the results. Until then, it remains nothing more than a video game.

Couldn't have said it better myself.

Hoop-98
16th September 2010, 16:22
True, and I wanted to play around with roll stiffnesses and other things, but I haven't really had a chance to just yet. Maybe in the next few days I'll be able to look at it again.

As for the wild guessing ... Yep that's all we are doing, and that is what gives me a bit of an uneasy feeling. If something so radical is to be accepted as a spec car, I really feel that more explaination is in order so that all of us die-hards with a small bit of mechanical know-how (you know the only fan base left, just about) would have a bit more buy-in with this car.

I don't understand why the front axle, suspension, steering axis etc are such a secret. It would be a lot easier to understand this vehicle if we knew about how the wheels steered.

rh

SoCalPVguy
16th September 2010, 18:06
Modeling schmodeling, As a professional engineer I have seen most models particularly for air conditioning and building energy use modeling to be worthless GIGO garbage in garbage out - so I have no confidence just because the Deltawing was "modeled". There is no proof that the modeling alogrythms are valid ... Who's model is it ? Whats the correlation between modela and actual performance... Of course the answer is .. none.

As for an earlier comment that the DW may perform like a three-wheeler- I agree and 3 wheelers are miserable in turing, anyone who had an old three-wheel ATV can attest, they quit making those for safety concerns beacuse they tipped over when steering... only 4 wheel ATVs are now available.

The only way to see how the DW races is build one and put it on the track.

Chris R
16th September 2010, 18:47
I don't understand why the front axle, suspension, steering axis etc are such a secret. It would be a lot easier to understand this vehicle if we knew about how the wheels steered.

rh

unless there is some patentable new device/mechanism involved that they need to protect the intellectual rights to prior to releasing info????

Hoop-98
17th September 2010, 00:17
Some educational reading...

http://www.rqriley.com/3-wheel.htm

rh

garyshell
17th September 2010, 00:31
There is no proof that the modeling alogrythms are valid ... Who's model is it ? Whats the correlation between modela and actual performance... Of course the answer is .. none.


And you would know this how? You may be right, but stating it as FACT is not. I have done some work with the folks at Dassault who make some of the most highend CAD and modeling software. They have lots of success stories of things designed purely in the digital domain that when produced in the real world worked exactly as modeled. They have done this in automotive, aviation, aeronautics and other arenas.

As with any item, of course the final step is to build it and test it, so I do agree with this last sentence:


The only way to see how the DW races is build one and put it on the track.


Gary

grungex
17th September 2010, 04:25
http://transmission.blogs.topgear.com/2010/09/16/series-15-outtake-ken-block-vs-reliant-robin/

Mark in Oshawa
17th September 2010, 08:44
Reading some of this stuff made my head hurt. Way beyond my education to speculate on, but I love the debate.

As I said, Chip is tossing money at this thing still, so he must see or know something that keeps him behind Bowlby. I hope this beast see's a race track for a public test...

Lousada
17th September 2010, 09:22
How much different will this thing drive compared to a normal car? How much practise would a driver need to safely jump in this car? (Would talented drivers even bother to learn this? Not if you want to go to F1...). They are having trouble finding 30 competent drivers as it is now...

I'm pretty sure it can be driven around any track. I'm less sure about the practical concepts though. Instead of putting one on the track, rather let one skid sideways across a wall. Or let one attempt to overtake another. The original design didn't even have rearview mirrors, can't see that working.

nigelred5
17th September 2010, 23:45
Modeling schmodeling, As a professional engineer I have seen most models particularly for air conditioning and building energy use modeling to be worthless GIGO garbage in garbage out - so I have no confidence just because the Deltawing was "modeled". There is no proof that the modeling alogrythms are valid ... Who's model is it ? Whats the correlation between modela and actual performance... Of course the answer is .. none.

As for an earlier comment that the DW may perform like a three-wheeler- I agree and 3 wheelers are miserable in turing, anyone who had an old three-wheel ATV can attest, they quit making those for safety concerns beacuse they tipped over when steering... only 4 wheel ATVs are now available.

The only way to see how the DW races is build one and put it on the track.

Unless of course your three wheeler is like this