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How would you build a car to compete for the X Prize?
4

How would you build a car to compete for the X Prize?

How would you build a car to compete for the X Prize?

(OP)
The rules for the Automotive X Prize (http://auto.xprize.org/) will be posted soon.

They think it will take less than 18 month to finance, design, provide a detailed production cost analysis, build and test a 100 mpg 4 passenger car that meets all the safety and emission standards world wide.

How do you think this can be done?

RE: How would you build a car to compete for the X Prize?

I imagine that most competitors will attempt to attain this goal through reduction in weight by using exotic or non-traditional body materials.  I don't think the engine technology will be anything radical or groundbreaking.  We will just have to wait and see.

Reidh  

RE: How would you build a car to compete for the X Prize?

Frankly, I wouldn't touch it, unless I had an engine/transmission design that was ready to go, and a body that was nearly there.

In order to meet crash regs you'll need at least three, and up to 50, prototypes.

Tooling for many parts is >6 months.

100 mpg is a nice round number, that's 2.5 litres per 100km, roughly. So if I were to take the best technology around, that gets ~ 70 mpg for a 4 seater... and doesn't meet US crash. If you were lucky you could add 150 kg to meet US crash (which will hit fc) , and then hybridise it, for a 50% improvement in fuel consumption.

Having said that if anybody wants a cynical mechanical engineer to work on concepts, timelines, and analysis, you know where to find me.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: How would you build a car to compete for the X Prize?

"The Automotive X PRIZE will invite teams from around the world to focus on a single goal: design viable, clean and super-efficient cars that people want to buy.

This will be a race for the ages, with major publicity and a big sack of cash waiting for the champion, and perhaps our future hanging in the balance."

Funny..  I thought the market was doing that already.

Mike Halloran
Pembroke Pines, FL, USA

RE: How would you build a car to compete for the X Prize?

First of I don't think it can be done in the time frame.

They ask for production costs. Do they have a maximum cost target, as obviously complex design and exotic materials can help.

Are there any performance criteria like acceleration, parking ease, external vision in all directions, cabin temperature, top speed, hill climbing, road holding, ride comfort, cabin space, luggage capacity etc etc etc.

I would think the best design concept would be a long narrow car with the passengers sitting in line slightly skewed so the foot wells extend to beside the seat in front. Head room would be very tight. Large passengers would not fit, the roof would probably be a solar cell.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

RE: How would you build a car to compete for the X Prize?

(OP)
Here is a link to the first presentation http://xprize.acrobat.com/p92151066/

Have to go skiing so I will check in later.

RE: How would you build a car to compete for the X Prize?

The automakers probably spend a billion dollars and take 3 to 4 years to get a new chassis/engine/transmission to market.  

This sounds like typical liberal academic fantasy.

RE: How would you build a car to compete for the X Prize?

I suppose its time to introduce the di-lithium crystals (only naturally made), tranparent aluminum, and of course ion drive.  We've lost Engineer Scott, but there's probably somebody from Berkley waiting in the wings.  Last time this contest had entries at our place, most didn't survive the car wash.  Oops...

My guess its a hydrogen fuel-celled electric golf cart sized entry with solid tires, little suspension, and 0 to 60 mph time in the 2 dozen range.  

RE: How would you build a car to compete for the X Prize?

I guess it will be thought of as an abominable idea, but how about 250cc two-stroke engine, with a good rotaty valve (say, variable timing) and CVT? Could that get near the fuel consumption on a light car, with reasonable power output?

RE: How would you build a car to compete for the X Prize?

Has to meet emissions. read the rules.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: How would you build a car to compete for the X Prize?

Greg, I think 250cc will meet the emissions even without variable valve timing (but I proposed it to get better fuel consumption/emissions across the whole range of revs)- at least, I think they're still sold in bikes in EU.

RE: How would you build a car to compete for the X Prize?

(OP)
I doubt any 2 stroke gas engine can meet the required pollution requirements.

The one lacking requirement in the rules is the required production cost.

My interest is the mainstream class vehicle. It seems you need to improve existing car fuel mileage by 3 times, yet maintain the acceleration performance and have a high top speed. The acceleration and top speed will make for design difficulties.
1. Can enough weight and aerodynamic resistance savings make this possible at the required sale price?
2. How many man hours should it take to design the body, frame and suspension?

RE: How would you build a car to compete for the X Prize?

1) well, that's just engineering. I can see it happening  so long as all the things that are poorly defined in the rules get left out. No crash, no airbags, no durability etc etc.

2) To what standard? Why not just buy an Audi A2 and fit your powertrain to it?

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: How would you build a car to compete for the X Prize?

(OP)
The problem I see with using an existing car is getting past the production cost requirement. What car manufacture would quote selling a partially built car for drive train and control retrofit?
Page 10 of the draft rules is about safety and it does specify UNECE or US FMVSS compliance.
I have ask APX for clarification of the target manufacture cost, if there will be extensions if no one qualifies in 2008 and have signed up for the Letter of Intent to find out more and see if there really is people to invest in doing this type of project.
1. In 10,000 per year manufacturing quantities what are some of the more cost effective methods to build the frame and body?
2. Would it be faster and or less expensive to subcontract out the crash analysis, and body CFD?
Estimating what it is going to cost and how long it will take to get to race day seems very difficult.

RE: How would you build a car to compete for the X Prize?

Ten thousand units a year is a horrible production rate to design for.  It's too high for hand- building, and too low to justify serious automation.  




Mike Halloran
Pembroke Pines, FL, USA

RE: How would you build a car to compete for the X Prize?

Mike
Production seems impossible to do without body in white technology, from what little I know it would take stampings and robotic welds to accomplish 38 cars a day or is my calculation way off...

Cheers

I don't know anything but the people that do.

RE: How would you build a car to compete for the X Prize?

I get 50 cars a day for 200 working days, which used to be the standard automotive year, allowing for weekends and shutdowns.

I worked in Ford's axle plant in the sixties.  Our normal production rate was 10,000 carsets a day, or 2 million a year.  That was for all car and light truck lines combined, so figure 1/10 of that, or 1000 cars a day, or 200,000 cars a year, for a successful line.

Further corroboration: GM killed the fourth generation Camaro/Firebird for low sales, and they sold an average of almost 80,000 cars a year for model years 1996..2001.

By way of illumination, Corvette sales for the same period averaged 27,427 cars/year.  We know the Corvette survives partly as a flagship and partly because of a lot of internal and external zealots.

Let's look at a lower production car; the Porsche Boxster, of which just over 200,000 have been built in 14 years, for an average of 14,285/year.

Are there enough green zealots who will _say_ they'll buy 10,000 tiny, slow cars a year?  Probably.  Will they pay somewhere upward of $50,000 for it?  Probably not.  Could anyone build it to sell for less than that?  Not if they have to buy any tooling.





Mike Halloran
Pembroke Pines, FL, USA

RE: How would you build a car to compete for the X Prize?

"Not if they have to buy any tooling."

Which of course is what Greg said, in far fewer words.

Mike Halloran
Pembroke Pines, FL, USA

RE: How would you build a car to compete for the X Prize?

(OP)
The Automotive X Prize Mainstream car entries can’t be tiny or slow. It must go 0-60 in 12 seconds, have a minimum 100 mph top speed and fit 4 people in the 95 percentile in size. Not that I know how big that is.

RE: How would you build a car to compete for the X Prize?

I'll find the latter out, 6'2 at a rough guess. http://www.cdc.gov/niosh/pot_anth.html

6'1.3" not a bad guess!

Looking through the rules I've got to say it is a beauty contest. Many aspects of the design are judged by what is appropriate, or whatever, by a panel.

They won't release the route over which the fuel consumption/speed is to be measured. This is to prevent 'gaming', or as engineers call it, optimisation.

The crash requirement is going to be very expensive.

and as I've pointed out, the timing is ridiculous.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: How would you build a car to compete for the X Prize?

The rules require meeting tier II bin 5 emissions. If you plan on using a combustion engine, that's not likely to happen unless you use a production engine with the emission control system already in place.

RE: How would you build a car to compete for the X Prize?

Hey sports fans:
Available elsewhere in the world, but not in the US, are nice, 2 seaters cars that reach more than double the CAFE of ours (the Ford KA for example) and meet all Euro standards for crash and emissions.  Hmmm.  It seems that some tweaking of that package would almost meet the X-Auto platform (hybridize most likely).

The claims that they are not available here in the US due to lack of customer acceptance (too small, too slow, dangerous, hogwash!) and other yackety yack stuff.

While in Europe recently, I had an opportunity to drive a nice 2 seater that altough was tight for my 6 foot 3 inch frame, was workable.  That car brought me well over 40 mpg at a performance level I could live with.  I see them in Mexico frequently but not in Canada.

Sign me as frustrated by the selection of world cars not available here in the US.

Franz

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RE: How would you build a car to compete for the X Prize?

You could restore a King Midget...

Mike Halloran
Pembroke Pines, FL, USA

RE: How would you build a car to compete for the X Prize?

(OP)
I don’t think there is any choice but to use a combustion engine in the main stream class, the energy density, cost of manufacture and weight penalties of electric drives will be their limitation. Until the target sales price is established there is no way of knowing what technologies can be used.

RE: How would you build a car to compete for the X Prize?

I guess I have a lot to learn about production rates..
Of course in my field we have parts per day not parts per second..

The 100 MPG will eliminate the use of ethanol


Cheers

I don't know anything but the people that do.

RE: How would you build a car to compete for the X Prize?

Get 12.5 to 1 compression ratio engine (<.5 liter) burning pure o-xylene which has 115% more energy per gallon than diesel and 100+ octane rateing.

RE: How would you build a car to compete for the X Prize?

dcasto,

The rules limit your selection of fuels:

"At this point, we expect to provide gasoline, diesel, electricity, natural gas, bio-diesel, and E85; the final list will be determined after initial applications are reviewed (additional fuels will require a clear business case that a vehicle using a non-mainstream fuel can succeed in the marketplace within a few years)."

RE: How would you build a car to compete for the X Prize?

thundair,

The contest is for 100 MPGequivalent, meaning that the thermal values of the fuels are taken into account relative to gasoline and there are corrected (and different) MPG values for fuels other than gasoline.

RE: How would you build a car to compete for the X Prize?

"The Automotive X PRIZE will invite teams from around the world to focus on a single goal: design viable, clean and super-efficient cars that people want to buy"  The problem is in that last bit.Its the market (Mike mentions above) If people wanted to buy clean super-efficient cars the roads would be clogged with them. Its not a technological problem,its more a public policy issue. So until fuel gets a lot more exspensive the the roads will continue to be clogged with cars trucks & SUVs that are about as heavy and efficient as they were 50 years ago.               Happy Motoring

RE: How would you build a car to compete for the X Prize?

Ref GMIracing's ref to the VW 'One Litre Car' project.

This 'One Litre Car' nomenclature means 100 km (62 miles) on one litre of fuel (about 288 mile/imperial gallon or 244 mile/US gallon).

Just-Auto.com had an item on this last week. VW's Dr Ferdinand Piech provided the following press release:

Quote:

Volkswagen will build a one litre car within the next three to four years, according to supervisory board chairman Ferdinand Piech.

Piech told Braunschweiger Zeitung, a newspaper local to the Volkswagen Wolfsburg site, that a one litre car (consuming just one litre of fuel for every 100km [60 miles] driven) had been made possible by falling prices for lightweight body parts and in particular for plastic parts.

Piech said a plastics manufacturer had told hime that parts that currently cost EUR35,000 to produce would cost just EUR5,000, meaning that they become economically viable. "That was not possible in my time," said Piech, formerly CEO of Volkswagen. "This is progress."

According to dpa-AFX, Piech was driven to his last annual general meeting as CEO in a small two-seat one litre car prototype. The car had a carbon body and consumed just 0.89l of fuel per 100km.

Piech was critical of his successor Bernd Pischetsrieder who ceased development work on both the one litre car and a cheaper-to-produce three litre version.

With Martin Winterkorn now heading up the VW Group, Piech said that the cars would be revived after a development period of three to four years.

Bill

RE: How would you build a car to compete for the X Prize?

"If people wanted to buy clean super-efficient cars the roads would be clogged with them.

FINALLY!  A poster who understands the economics of the automotive business.  Way to go FoMoCoMoFo.

RE: How would you build a car to compete for the X Prize?

Hybrid Diesel.  New low sulphur diesel systems with series/parallel capability. are the ticket.  The efficiencies and low weight are here today.

RE: How would you build a car to compete for the X Prize?

Low weight, right a titanium car or composites from a stealth airplane. Just think how cool and the appeal to macho SUV people.  Don't worry about the cost, we'll get to that later.

RE: How would you build a car to compete for the X Prize?

Franz-
Blame your government - specifically, NHTSA - for the unavailability of micro-cars in the U.S.

Mike:
10,000 units per year is not at all too small for hand-building.  We build up to 40,000 trucks a year by hand, most to individual specific customer order.

But as to designing a car to get the "X-Prize:"  First you get all the drugs you can find...

RE: How would you build a car to compete for the X Prize?

10000 cars a year is doable by hand, it is twice what Ferrari do, but you'll still end up with about the same level of automation as say a 1980s Japanese plant - lots of jigs and handling devices, just not many robots.

You will have a production line, it may be a push-along one.

Cheers

Greg Locock

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