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Deltawing for LeMans in 2012


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#101 cheapracer

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Posted 13 March 2012 - 13:57

The racing line is more or less clear over it's entire width, it's not like the highway where trucks make two grooves.


For example, Indy at LeMans ..

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#102 Ross Stonefeld

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Posted 13 March 2012 - 13:59

Yeah some parts of Le Mans are like that, but that's a problem for all cars.

#103 Slowinfastout

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Posted 13 March 2012 - 14:03

You guys bring an interesting topic anyway, I would love to hear about the car specific issues (setup, etc..) the team are facing as they get to grips with this thing..

#104 cheapracer

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Posted 13 March 2012 - 14:06

Yeah some parts of Le Mans are like that, but that's a problem for all cars.



The line is lightest on the right groove where 80% of the weight and friction takes place, darker on the left groove where less happens and quite dark in the middle - take the colour differences as traction grip levels obviously the darkest being the slipperiest and right where the Deltawings front wheels will traverse.


#105 Ross Stonefeld

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Posted 13 March 2012 - 14:13

The Truck Tracks© are parallel to the paint lines, not the racing line. So the Deltawing won't be straddling the grooves any more than a normal car would.

#106 Slowinfastout

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Posted 13 March 2012 - 14:15

The line is lightest on the right groove where 80% of the weight and friction takes place, darker on the left groove where less happens and quite dark in the middle - take the colour differences as traction grip levels obviously the darkest being the slipperiest and right where the Deltawings front wheels will traverse.


It's hard to tell if this will be significant though..

I'm not sure how to word it, but it seems to me the Deltawing will always have at least one front wheel on what is the optimal part of the groove. (it's funny enough this car already managed to split 'the groove' into different parts though)


#107 cheapracer

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Posted 13 March 2012 - 14:20

The Truck TracksĀ©


:lol:

So the Deltawing won't be straddling the grooves any more than a normal car would.


Of course it will be, at that apex right there the Deltawings front wheels will be smack in the middle on one years worth of car's and truck's dripping oil as well as unused/unworn (rougher) surface.

#108 desmo

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Posted 13 March 2012 - 14:52

The more I think about this concept the more sense it makes to me. Hugely rear biased weight distribution, aero CP likewise hugely rear biased, a long lever out front to turn a car that won't need a lot of lateral impetus to turn in, low weight, low drag... Will it work? Who knows, but I doubt Michelin and Nissan would get on board if it didn't have real promise. Seems a natural for the application of advanced ASC, sort of analogous to modern FBW fighter planes that are intrinsically unstable but make a virtue of it through electronic control.

#109 desmo

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Posted 13 March 2012 - 15:02

:lol:



Of course it will be, at that apex right there the Deltawings front wheels will be smack in the middle on one years worth of car's and truck's dripping oil as well as unused/unworn (rougher) surface.


On the other hand the car shouldn't need much lateral grip up front to steer, the front wheels are more like the rudder on a boat turned backwards, more a trimming mechanism than a conventional highly loaded steering axle.


#110 MatsNorway

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Posted 13 March 2012 - 18:20

On the other hand the car shouldn't need much lateral grip up front to steer, the front wheels are more like the rudder on a boat turned backwards, more a trimming mechanism than a conventional highly loaded steering axle.


If so your not using the available grip good enough.. -> wearing the rears faster than a balanced car.

#111 desmo

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Posted 13 March 2012 - 18:31

Actually if the car is substantially lighter as appears there's no reason that should be the case. Is there?

#112 Ali_G

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Posted 13 March 2012 - 21:20

:lol:



Of course it will be, at that apex right there the Deltawings front wheels will be smack in the middle on one years worth of car's and truck's dripping oil as well as unused/unworn (rougher) surface.


As silly as this sounds, could the car be setup (using 4 wheel steering) so that the front of the car would hug the apex during everyone corner.

To do so might require the front wheels to steer in the opposite direction of movement with the rear wheels going the majority of the steering.

#113 Greg Locock

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Posted 13 March 2012 - 21:49

1) they had to do something to counter reduced interest among the younger audience

2)Various series have demonstrated that rule changes are not enough

3)they have done something reasonably significant that hasn't been tried before with 'open wheeler's

I'd guess that dollar for dollar a conventional car could be faster round a given circuit, that is not the point.

#114 PLAYLIFE

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Posted 13 March 2012 - 23:37

Despite liking the 'out of the box' thinking, I can't see it being anything less than a massive flop.

Even if it does drive reasonably under normal conditions how will it react when it becomes unstable and gets out of shape, especially through a quick corner? How do you 'correct' it?

#115 maxay1

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Posted 13 March 2012 - 23:45

Should be an interesting car, in terms of handling....it was pointed out on another forum that load transfer across an axle is inversely proportional to track width, while roll stiffness is proportional to the track width squared; the smaller front track will result in less roll moment reacted at that axle (obviously more at the rear). Does seem to have a large 'control moment capability', but without knowing much about tire construction, hard to say much.

Wil

#116 gruntguru

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Posted 14 March 2012 - 05:57

If so your not using the available grip good enough.. -> wearing the rears faster than a balanced car.

The rear will be carrying much more weight than the front. There is probably twice as much rubber on the road at the rear so they would need to wear at twice the rate anyway.

#117 cheapracer

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Posted 14 March 2012 - 08:40

Despite liking the 'out of the box' thinking, I can't see it being anything less than a massive flop.


Are you talking from a commercial POV or a car dynamics POV? First will be a huge publicity (albeit momentary) success and will be quickly forgotten ala P34 Tyrell 6 wheeler so I guess you're correct but that latter is untrue and the car will perform to all it's parameters and will be successful primarily because it is unregulated running against regulated cars - regardless of how bad it may be on equal ground, the 'half weight' advantage (475 Vs 900kgs) is a huge one.


Even if it does drive reasonably under normal conditions how will it react when it becomes unstable and gets out of shape, especially through a quick corner? How do you 'correct' it?


Correction is the same as any normal vehicle, it might suffer from some snap oversteer occasionally but will snap back into place equally as fast because of it's very low polar moment and a triangular footprint vehicle's ability to change yaw rapidly.

By the way, as I mentioned earlier about 3 wheelers handling opposite to what most people think, did anyone see the Morgan 3 wheeler on Top Gear and it's horrible understeer ...



#118 jatwarks

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Posted 14 March 2012 - 08:41

I'm beginning to think it might be worth giving it the benefit of the doubt until it's proved otherwise.

It's an interesting exercise, certainly.

I'm now looking forward to its debut race. The proof of the pudding, and all that.


#119 saudoso

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Posted 14 March 2012 - 12:38

Cheap, where did that 52" come from?

Edited by saudoso, 14 March 2012 - 12:39.


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#120 cheapracer

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Posted 14 March 2012 - 12:58

Cheap, where did that 52" come from?


52"??

Did you mean the 52 seconds for the lap time?


#121 saudoso

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Posted 14 March 2012 - 13:30

Yep, isn't ' for minutes and " for seconds?

Edited by saudoso, 14 March 2012 - 13:30.


#122 Hun200kmh

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Posted 14 March 2012 - 16:36

If you watch the inboard video of the car around Buttonwillow's west loop you'll find it completes a lap in 52 seconds (I'd say a litle under that, 51 something). Of course the video can be "fabricated" to make us have that illusion, but it's what it seems.

One interesting thing to also get from that video is that the car apparently has no "paddles", Marino is changing gears using a sequential shifter.

#123 cheapracer

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Posted 14 March 2012 - 16:46

Yep, isn't ' for minutes and " for seconds?


Sorry Mate, yes it is - I was seeing 52 inches!


the car apparently has no "paddles", Marino is changing gears using a sequential shifter.


Well it seams you should not use a seamless box when you can use a non-seamless box that seams to be closer to seamless than a seamless seams to be - or so it seams we have been told seamlessly.

Edited by cheapracer, 14 March 2012 - 16:57.


#124 munks

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Posted 14 March 2012 - 19:15

Well it seams you should not use a seamless box when you can use a non-seamless box that seams to be closer to seamless than a seamless seams to be - or so it seams we have been told seamlessly.


If only this quote was attributed to Irish poet Seamus Heaney, it would have been perfect.

#125 Ross Stonefeld

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Posted 14 March 2012 - 19:20

Pffft, aren't the Irish getting enough freebies this week?

#126 saudoso

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Posted 14 March 2012 - 19:45

Sorry Mate, yes it is - I was seeing 52 inches!


That's allright. Me don't consider the inches that much...

Now where those other times come from? From what I figured they ran the track #24 (west loop only) and I can just find times for the two loops (#1, #13, #18) and those are around 2 minutes.

#127 Hun200kmh

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Posted 14 March 2012 - 22:29

Well it seams you should not use a seamless box when you can use a non-seamless box that seams to be closer to seamless than a seamless seams to be - or so it seams we have been told seamlessly.


It seams I wasn't clear, because I don't really care about the seamlessness of the box, but with the fact that seamingly the DeltaWing driver will need to take his right hand off the wheel to change gears. So, my observation was more about paddles and sticks than it was about the boxes they operate.


Now where those other times come from? From what I figured they ran the track #24 (west loop only) and I can just find times for the two loops (#1, #13, #18) and those are around 2 minutes.


I guess from here:
Posted Image

Edited by Hun200kmh, 14 March 2012 - 22:29.


#128 saudoso

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Posted 14 March 2012 - 22:47

OK, tks

#129 Ross Stonefeld

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Posted 15 March 2012 - 11:17

Won't those laptimes be from road cars?

#130 saudoso

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Posted 15 March 2012 - 11:33

I guess so. I'm wondering if Cheapy's time for Road Atlanta also are.

#131 sblick

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Posted 15 March 2012 - 12:32

My friend says he can get his Titan Formula Ford around in the low 63's. It is an old FF in years, but very well prepared. He said a 62 in his FF car should be doable. Maybe that will help out a little on lap times also. Oh and yes that is on the west loop only

#132 BRG

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Posted 15 March 2012 - 12:55

My friend says he can get his Titan Formula Ford around in the low 63's. It is an old FF in years, but very well prepared. He said a 62 in his FF car should be doable. Maybe that will help out a little on lap times also. Oh and yes that is on the west loop only

Thanks, because when I watched the video, my first thought was that a good F. Ford would get through the corners a lot faster than that.

#133 arttidesco

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Posted 15 March 2012 - 13:24

Looks like Nissan has got involved with the Deltawing LM Project ????

#134 Ross Stonefeld

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Posted 15 March 2012 - 14:04

I guess so. I'm wondering if Cheapy's time for Road Atlanta also are.


That was going to be my next question, because I thought he was comparing to C6 GT2 times.

#135 sblick

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Posted 15 March 2012 - 16:26

The word from a Nissan GT Academy participant was the Delta Wing looked really good at Sebring and had no problems keeping up with other cars. What "other cars" means I haven't been able to suss out. Rumor is after LeMans they are going to bring the car back to the US and do ALMS. Road America ticket sales person was saying it had a good chance of being there. I hope it hits objectives in LeMans so we can see it here.

#136 24gerrard

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Posted 16 March 2012 - 12:49

Has anyone thought to ask what kind of differential and differential control this thing uses?

#137 murpia

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Posted 16 March 2012 - 13:46

Has anyone thought to ask what kind of differential and differential control this thing uses?

If you take a look at the Racecar interview with Ben Bowlby here:

http://gb.zinio.com/...7...ev=sub&p=44

he describes a form of torque vectoring diff.

But, I don't see how this works as a torque vectoring diff. It's more a speed vectoring diff. Any difference in torque at the rear axle would have to come via the rear tyre slip ratios, only loosely coupled to the speed difference. And not responsive or accurate enough in my opinion to allow the driver control effect Bowlby describes.

This is in contrast to recent torque vectoring diffs described by Mistubishi, Honda & BMW which shunt torque independent of speed.

Of course, Bowlby may have been misquoted or the description otherwise mangled by Racecar.

Another 'active' torque vectoring diff design recently described by Oxford Brookes University has the same issue.

Regards, Ian

#138 24gerrard

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Posted 17 March 2012 - 11:55

If you take a look at the Racecar interview with Ben Bowlby here:

http://gb.zinio.com/...7...ev=sub&p=44

he describes a form of torque vectoring diff.

But, I don't see how this works as a torque vectoring diff. It's more a speed vectoring diff. Any difference in torque at the rear axle would have to come via the rear tyre slip ratios, only loosely coupled to the speed difference. And not responsive or accurate enough in my opinion to allow the driver control effect Bowlby describes.

This is in contrast to recent torque vectoring diffs described by Mistubishi, Honda & BMW which shunt torque independent of speed.

Of course, Bowlby may have been misquoted or the description otherwise mangled by Racecar.

Another 'active' torque vectoring diff design recently described by Oxford Brookes University has the same issue.

Regards, Ian


The electric motor input at the differential is essential to the cornering capability of this vehicle.
I mentioned my ideas for the concept on another thread applied to a tadpole layout.
My system does not need a differential however.
My ESERU allows such control without one.

#139 cheapracer

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Posted 17 March 2012 - 14:14

I guess so. I'm wondering if Cheapy's time for Road Atlanta also are.


Of course, wouldn't be consistency otherwise.


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#140 Bloggsworth

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Posted 20 March 2012 - 22:31

Pffft, aren't the Irish getting enough freebies this week?


No. They were trashed by England at Twickenham.

#141 RDV

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Posted 23 March 2012 - 14:03

...this weeks test times at Sebring, after 12h race, Audi Hybrid 1'43.2, DW 1'53.8. Use of manual shift due to software issues between engine (blipper, cut), paddle shift software and gearbox, using plan B to get miles on it. Diff used at moment = fully open, torque steering not connected for same reason, too many software and component items to be tested, and as main objective is to develop tyres for Michelins second iteration on design and compounds it is running in KISS mode. If anything torque steering will calm down front end, it is too aggressive at moment, needs less caster and slower steering.
Biggest challenge will be to get car in 24h reliability mode...79 days to go, and many new features to be ironed out. Test driver Comas comments on Buttonwillow test.

#142 Ross Stonefeld

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Posted 23 March 2012 - 14:16

So someone who knows what's going on with the DW thinks it's steering a little too much?

#143 cheapracer

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Posted 23 March 2012 - 14:53

So someone who knows what's going on with the DW thinks it's steering a little too much?


3 wheelers can change yaw rate much faster as I mentioned in post #117, that's not a secret about 3 wheelers..

#144 Ross Stonefeld

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Posted 23 March 2012 - 14:58

It has 4 wheels.

#145 Slowinfastout

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Posted 23 March 2012 - 14:59

It's hard for me to get the full picture in my head with the driving characteristics this car should have, but running a fully open diff surely should make a massive difference about getting the power down and the car wanting to turn more than it should..

#146 hogits2

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Posted 23 March 2012 - 15:13

3 wheelers can change yaw rate much faster as I mentioned in post #117, that's not a secret about 3 wheelers..


Given same polar moments etc. what would make the difference?

( Not counting 'Morgansteer' & Clarkson)

Edited by hogits2, 23 March 2012 - 15:20.


#147 Tenmantaylor

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Posted 23 March 2012 - 15:31

I like the latest concept but it seems it's going to be a nightmare getting this thing turned into corners, narrow front track and no front downforce? Or is their some secret underbody aero I can't see that keeps an equal C of Downforce? How are they going to acheive the grip levels from the front tyres to have a decent Centre of Grip? From my untrained eye I'd say there's going to be so much more grip at the rear. Unless the rear tyres are a lot skinnier than they are letting on that is.

#148 saudoso

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Posted 23 March 2012 - 15:48

There is a difference between steering fast into the bend and completing the turn fast.

Given enough leverage a skateboard wheel will push the car into a turn, so I can't see this being a problem.

My beef with the concept is what happens around. The thing has a huge rearward brake bias. It will suffer massive weight transfer between the rear wheels and the inside rear will lock easily. Probably disrupting the outer one and having it locked also. I guess this was reported from the first test. So you have a car that loses a lot of braking power when it turns in. And this is not the recipe for a fast racing car.

When you look at a square care, you will see it braking heavily into the turn, the weight transfer from rear to front compensating the in/out transfer and only the inner rear wheel really getting silly. You lose way less braking power in a car with an already front biased braking setup.

The other big issue is what will happen when the balance is disrupted. When it's touched by another car or when the driver makes a mistake and swallows the curbs.

#149 Slowinfastout

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Posted 23 March 2012 - 15:48

Like desmo said on previous page, the weight distribution is all the way to the back and the front wheels are such a far way in front that you effectively have a big lever effect, so the front tyres don't have to work very hard to make the thing turn.

Kinda like you can turn this thing around relatively easily.
Posted Image

#150 hogits2

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Posted 23 March 2012 - 15:54

Like desmo said on previous page, the weight distribution is all the way to the back and the front wheels are such a far way in front that you effectively have a big lever effect, so the front tyres don't have to work very hard to make the thing turn.

Kinda like you can turn this thing around relatively easily.
Posted Image



Now I see where their inspiration came from.

(OT. Have you ever picked up the front of one and the water all rushes to the back and it stands on its backend and then you run away as the workmen are coming back.)