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driverless cars to hit california ( sorry!)


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#201 NTSOS

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Posted 18 October 2012 - 00:58

I wonder what would have happened if they had heeded all of the stall warning indicators, audio, stick shake, buffeting and simply pushed forward on the stick?

I think that a commercial pilot with glider expertise would have  instinctively put the nose down as opposed to yanking back on the stick as the Airbus pilot apparently did.

John

Edited by NTSOS, 18 October 2012 - 02:49.


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#202 bigleagueslider

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Posted 18 October 2012 - 02:02

Rather than compare commercial aircraft flight safety to that of privately-owned "driverless" automobiles, maybe a better comparison would be private general aviation aircraft to private driverless vehicles. And here's the statistic regarding GA accidents that should frighten you: 100% of GA aircraft accidents result in lawsuits against the engine and airframe OEMs. In the US alone, there are several million auto accidents each year. Can you imagine the litigation nightmare that could possibly result?

#203 gruntguru

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Posted 18 October 2012 - 02:09

In the US alone, there are several million auto accidents each year. Can you imagine the litigation nightmare that could possibly result?

There won't be any involving driverless cars. :)

#204 MatsNorway

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Posted 18 October 2012 - 06:21

Yeah, it appears several people still have their fingers in their ears, unable to use them to type their own web searches or to navigate this thread to read things that have been stated repeatedly.


We are talking about a commercially available car. so don`t give them/us this bs.

#205 Greg Locock

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Posted 18 October 2012 - 07:00

Why the tude?

Anyway, Volvo have publicly announced that by 2020 they intend to have cars that essentially will not have serious accidents. If we stretch that a little to mean they won't hit anything, then all you need is a brick on the throttle and to randomly wiggle the steering wheel and eventually, on an island, you'll arrive at your destination.

#206 Youichi

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Posted 18 October 2012 - 08:23

We are talking about a commercially available car. so don`t give them/us this bs.


No we weren't, there was no mention of comercial availability in the original question.

Autonomous vehicle operation in unprogrammed city/suburban traffic in normal conditions interacting with human drivers...give me a forecast, futurists. In what year will this occur?





#207 Bloggsworth

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Posted 18 October 2012 - 12:24

On a related subject, I see that Nissan are to introduce steer-by-wire cars in 2 years, on the grounds that the drivers will no longer have to put up with the feedback from the road surface through their hands - Well I won't be buying one of those; I regard feedback through the steering wheel as an essentiail part of detecting the condition of the road in adverse conditions.

#208 gruntguru

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Posted 18 October 2012 - 12:37

They may be onto something. They just need to fine tune the system, make it work "at a red light, or a stop sign" and all our issues would be solved.

As long as it doesn't infringe any of Google's atheistic patents.

#209 Ross Stonefeld

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Posted 18 October 2012 - 13:03

On a related subject, I see that Nissan are to introduce steer-by-wire cars in 2 years, on the grounds that the drivers will no longer have to put up with the feedback from the road surface through their hands - Well I won't be buying one of those; I regard feedback through the steering wheel as an essentiail part of detecting the condition of the road in adverse conditions.



Maybe you should slow down so you aren't testing the limits of the tire/tyre.

#210 Dmitriy_Guller

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Posted 18 October 2012 - 13:05

Anything ending with the "True story..." is at least 95% guaranteed to be an urban legend or a hoax. On top of that, blind religious faith doesn't work like that. Religious people are very careful to always leave plausible deniability for cases when God doesn't act, and a car wrapped around the tree doesn't quite leave much room for it.

#211 MatsNorway

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Posted 18 October 2012 - 14:18

One aspect not mentioned i believe.

will the self driving car be allowed to break the speed limit to avoid a accident. Or run across a double line and so on.



Maybe you should slow down so you aren't testing the limits of the tire/tyre.


Snow/ice makes that hard sometimes. going up a steep hill and so on.



#212 Bloggsworth

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Posted 18 October 2012 - 14:50

Maybe you should slow down so you aren't testing the limits of the tire/tyre.


Tell that to the weather, the steering suddenly going light may be the only warning you get of black ice.

#213 munks

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Posted 18 October 2012 - 16:24

On a related subject, I see that Nissan are to introduce steer-by-wire cars in 2 years, on the grounds that the drivers will no longer have to put up with the feedback from the road surface through their hands - Well I won't be buying one of those; I regard feedback through the steering wheel as an essentiail part of detecting the condition of the road in adverse conditions.


"on the grounds that the drivers will no longer have to put up with the feedback"

Not sure if serious ... ???

#214 munks

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Posted 18 October 2012 - 16:26

OK, I see you were making things up now.

"Nissan says that not only will feedback be more direct, it will also be adjustable." (from Link)

EDIT: But, given that they still have to have a backup mechanical link, I'm not sure what real problem they are solving here. If it was space-saving, great, but it's not.

Edited by munks, 18 October 2012 - 16:29.


#215 Bloggsworth

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Posted 18 October 2012 - 17:32

"This transmits the driver's intentions to the wheels even faster than a mechanical system and increases the direct driving performance feel by quickly and intelligently communicating road surface feedback to the driver," the automaker said.

"For example, even on a road surface with minor ridges or furrows, the driver no longer has to grip the steering wheel tightly and make detailed adjustments, so traveling on the intended path becomes easier."


How could it react more quickly that a direct mechanical link to the front wheels? Who do you know that grips the steering wheel "tightly"? Who makes detailed adjustments, and what are these detailed adjustments - Sounds to me as if they are inventing a solution for a problem which doesn't exist...

Edited by Bloggsworth, 18 October 2012 - 19:10.


#216 MatsNorway

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Posted 18 October 2012 - 17:56

They probably want to eliminate torque steer and wheels following the road track stuff. by having a coupling that opens and will close if say the engine oil drops or electricity drops you can push things around and dampen a lot of the shocks before the coupling hits the actual steering mechanicsm.

Electrical servos (assuming, avensis got this) are silly.



#217 Greg Locock

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Posted 18 October 2012 - 23:18

How could it react more quickly that a direct mechanical link to the front wheels?

It could react more quickly than a mechanical system. For example, BMW in the 1990s had a torsional isolator in the steering column in the 5 series. This was effectively a 3 Hz low pass filter. I'm sorry to keep picking on your apparent lack of knowledge, but you are stumbling from factoid to random assertion to factoid and back again. We get it, you don't like electronic thingies in your car. Fine. Don't buy a car with them in. That is a choice you have.

#218 gruntguru

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Posted 19 October 2012 - 04:53

will the self driving car be allowed to break the speed limit to avoid a accident. Or run across a double line and so on.

Why not? It would be up to the programmer to assign priorities. Accident avoidance comes before road rules - same as for human drivers.

#219 Bloggsworth

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Posted 19 October 2012 - 08:25

It could react more quickly than a mechanical system. For example, BMW in the 1990s had a torsional isolator in the steering column in the 5 series. This was effectively a 3 Hz low pass filter. I'm sorry to keep picking on your apparent lack of knowledge, but you are stumbling from factoid to random assertion to factoid and back again. We get it, you don't like electronic thingies in your car. Fine. Don't buy a car with them in. That is a choice you have.


From "A BMW with a 3Hz low pass filter" you extrapolate all cars, and from this you also infer that electrically steered cars will not have any decoupling from road shock, that the actuator will be solidly coupled to the steering arms.

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#220 Ross Stonefeld

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Posted 19 October 2012 - 10:27

Dude you've been extrapolating for 6 pages from your own anecdotes.

#221 munks

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Posted 19 October 2012 - 14:07

From "A BMW with a 3Hz low pass filter" you extrapolate all cars, and from this you also infer that electrically steered cars will not have any decoupling from road shock, that the actuator will be solidly coupled to the steering arms.


OK, how about this: electrons or wireless signals can move faster (by wire or by air) than shock waves do through the steering system.

That said, the steer-by-wire system presumably has sensor readings from the hub or steering link, from which they do some processing with the information, and then finally have to actuate a motor to provide feedback. I believe the last one would take the most time, but I don't know off-hand what the latency there might be.

#222 Magoo

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Posted 19 October 2012 - 20:30

May you never be stuck in an automated call center.

#223 Bloggsworth

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Posted 20 October 2012 - 09:00

Dude you've been extrapolating for 6 pages from your own anecdotes.


They were not anecdotes, they actually happened. I have asked questions to which I have had no answers but "Computers are better" - What we need here is someone who is actually working on this project who can actually answer the questions rather than make statements abot the generalities of AI in computers without actually addressing the specifics. If someone from Google comes on here and tells us that they have driven cars through the streets of London for 3 years accumulating information on traffic patterns, pedestrian behaviour, the effect of rain on oil soaked roundabouts in dense traffic; and from this information they have written algorithms which can allow for the fact that a tourist might look left instead of right when stepping off a kerb...

Edited by Bloggsworth, 20 October 2012 - 11:11.


#224 Ross Stonefeld

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Posted 20 October 2012 - 10:13

They were not anecdotes, they actually happened.


Have I been labouring under the incorrect assumption that anecdote meant limited rather than false?

#225 Bloggsworth

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Posted 20 October 2012 - 11:37

Have I been labouring under the incorrect assumption that anecdote meant limited rather than false?


Literally you are quite correct, but the implication was that they aren't relevant to the discussion. I have never said that computers won't be able to do these things, I have been asking what "arrangements" have been made in the software and database to deal with them - All I have heard in reply is that I'm an idiot because computers will be able to deal with them, no evidence, no proof, no references to published documents explaining how the algorithms will deal with the situations outlined - Perhaps it will be like the London Underground train I was on yesterday which refused to move until after the driver had done a Ctrl-Alt-Del three times over 4 or 5 minutes. Now an underground train is pretty low on the scale of difficulties for autonomous control, and the system was able to stop all the trains behind us to prevent an accident; issues such as this must be publicly addressed, there must be no hiding behind warranties, no claims that sofware faults don't count, no slithering out with "We didn't know anybody would go there/do that" clauses.

Edited by Bloggsworth, 20 October 2012 - 11:37.


#226 Ross Stonefeld

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Posted 20 October 2012 - 11:45

Let's accept that the computers can't save the situations you describe. My contention is that they are the exception rather than the rule and computer-driven driving will cut down on the far more common and avoidable accidents.

#227 MatsNorway

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Posted 20 October 2012 - 11:54

Why not? It would be up to the programmer to assign priorities. Accident avoidance comes before road rules - same as for human drivers.


Humans in say the other lane can do something irrational and a more serious accident the autonomus car can`t avoid will occur. say instead of getting a smashed rear end you end up in a front collision.

At that point you could also blaim the car. The risk is less of a problem perhaps with all cars being autonomus. But even then its there. If think that for this reason alone crash avoidance that means rulebreaking will not be allowed, at least in the beginning.

There is also the dilemma with the car being allowed to do something humans are not. unfair, What if and so on.

Edited by MatsNorway, 20 October 2012 - 11:56.


#228 Bloggsworth

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Posted 20 October 2012 - 13:20

Let's accept that the computers can't save the situations you describe. My contention is that they are the exception rather than the rule and computer-driven driving will cut down on the far more common and avoidable accidents.


My contention is that it is in the exceptional when accidents occur.

The other point is that the car manufacturing lobby is so strong that they will lobby governments and spend whatever they need to influence politicians the write the legislation regarding autonomous cars in favour of the manufacturers. We already have a parallel situation in the UK. If I buy a colour television/toaster/computer the Sale of Goods Act allows me redress for a foulty product for up to 5 or 6 years, the item has to be "Fit for Purpose"; intensive lobbying in advance of the introduction of this law ensured that it did not apply to cars, you can drive your car off the forecourt and have the wheels fall off, the engine blow up, the bodywork crack in half, and in law, all you can ask is that the company repair it to a satisfactory condition (Their satisfaction, not yours); you are not entitled to a replacement car - Now, OK, that's an extreme case, but variations on that theme happen all the time; my friend had the engine fall out of his Lancia, along with several hundred others, did Lancia fix it? No - Out of warranty mate. The fact that it was happening all over Europe, and was clearly a consequence of crap manufacturing held no weight.

You can be sure that the manufacturers of autonomous cars will want exclusions that will limit their liability in the event of death or injury owing to failures in the equipment.

#229 Bloggsworth

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Posted 20 October 2012 - 15:13

Is this the world's first fully autonomous airport?

#230 Greg Locock

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Posted 20 October 2012 - 20:48

Was the BMW 5 series criticised for lack of road feel, or poor steering? No it wasn't, in fact it usually rated very highly, which is why we were surprised by the isolator. Of course one you look at the yaw rate/steering wheel frequency response for a car it becomes obvious why attenuating the high frequency stuff doesn't hurt your ability to control the car.

There are really good reasons to go with steer by wire, a few moments of rational thought will probably get you there, BUT it is impossible to ignore the obvious objection. Perhaps they will go to a double or triply redundant system

#231 gruntguru

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Posted 21 October 2012 - 03:44

There is also the dilemma with the car being allowed to do something humans are not. unfair, What if and so on.

You will find that in most countries, humans are in fact allowed to break road rules if the only alternative is a collision.

#232 gruntguru

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Posted 21 October 2012 - 04:51

My contention is that it is in the exceptional when accidents occur.

You could scarcely be more wrong. Following tables lifted from http://www-nrd.nhtsa...Pubs/811059.PDF.

Posted Image
Most accidents occur with the car going straight, negotiating a curve or stopped



Posted Image
Men (generally more skilful in terms of car control, more reactive, more aggressive avoidance manouvres etc) have more accidents than women. As to age, it appears that the demographic including yourself (and myself) has very low accident rates so perhaps the skills you repeately trumpet are not present in other age groups. It seems you may be safer surrounded by driverless cars than ones driven by 16-25 y.o. males.


Posted Image




Posted Image

So pick through this one and tell me what percentage of accidents are due to lack of avoidance skills?

#233 Bloggsworth

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Posted 21 October 2012 - 09:00

If I'm driving in a straight line, fully concentrating, and someone who is obviously not paying attention turns across in front of me and I hit him, into which catagory of accident does that fall? Straight line, turning, inadequate surveillance? - Without knowing the questions, the answers are difficult to interpret and, as America has a huge number of straight roads compared to the UK, there will be far more straight line accidents, just as there may well be in Australia or Canada. What is tha "Weighting", what is being weighted? I would suggest that the majority of accidents are preceeded at some point by driving in a straight line - yes, I'm playing with you, but out of context, with no comparison with the number of vehicles on the road at any one time, 100% of the various accidents may only be 0.0001% of vehicles on the road at any one time, and thus a very small proportion of the time spent driving in a straight line may result in an accident. It also doesn't state whether these straight line accidents are single or multiple vehicle collisions.

There is no mention of whether or not these are single or multiple vehicle accidents, rather important when interpreting the statistics, for instance, is a freeway crash involving 100 cars counted as 1 or 100 accidents? Movement prior to suggests that at the moment of the accident perhaps a different movement was in progress, if we don't know what that is, how can we assess the importance of the unmentioned movement - I am assuming that if they meant "during the critical..." Semantics may seem like pedantry to some, but they are critically important when interpreting written reports of events.

#234 gruntguru

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Posted 22 October 2012 - 00:20

There is a lot more information in the original document. If you are interested in the minutiae follow the link. OTOH for the purposes of deciding whether human creativity is a reason to keep driverless cars off the road you only need to consult the last table:

Inadequate surveillance . . 20.3%
Internal distraction . . . . . .10.7%
External distraction . . . . . . 3.8%
Inattention . . . . . . . . . . . . 3.2%
Too Fast for conditions . . . . 8.4%
Too fast for curve . . . . . . . .4.9%
False assumption of other . . 4.5%
Illegal manouvre . . . . . . . . 3.8%
Misjudge gap or speed . . . . 3.2%
Overcompensation . . . . . . . 4.9%
Poor directional control . . . . 4.7%
Asleep . . . . . . . . . . . . . . . .3.2%
Heart attack . . . . . . . . . . . .2.4%
.
Spotted the trend yet? This are all distinctly "human" failings.
.
.
Lack of creativity . . . . . . . . .???%

#235 munks

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Posted 22 October 2012 - 01:13

I thought overcompensation referred to the type of vehicle you are driving, not why you crashed it???

#236 gruntguru

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Posted 22 October 2012 - 03:47

I thought overcompensation referred to the type of vehicle you are driving, not why you crashed it???

You mean like THIS.

#237 munks

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Posted 22 October 2012 - 14:46

You mean like THIS.


Hmm, yes, that really brings things to a head.

#238 Tenmantaylor

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Posted 22 October 2012 - 15:07

On a related subject, I see that Nissan are to introduce steer-by-wire cars in 2 years, on the grounds that the drivers will no longer have to put up with the feedback from the road surface through their hands - Well I won't be buying one of those; I regard feedback through the steering wheel as an essentiail part of detecting the condition of the road in adverse conditions.


I agree, although they could artificially recreate the feedback with an electric motor :lol:

You can be sure that the manufacturers of autonomous cars will want exclusions that will limit their liability in the event of death or injury owing to failures in the equipment.


This is probably the biggest hurdle for the technology to become a reality. At least if some idiot crashes at 60mph all by himself in a 30 zone it was his own dumb fault.

Edited by Tenmantaylor, 22 October 2012 - 15:12.


#239 Greg Locock

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Posted 22 October 2012 - 22:53

I agree, although they could artificially recreate the feedback with an electric motor :lol:

Yup, that's how they'll do it. There have been production cars with 100% assistance using HPAS, ie no real feedback.

The only useful signals to the driver are how much force he is asking for, and where he is on the curve of force vs slip angle. He'd also like to know if the brakes are pulling. All the other stuff you get as steering wheel torque is noise, not information.

Edited by Greg Locock, 22 October 2012 - 23:08.


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#240 munks

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Posted 23 October 2012 - 14:53

The only useful signals to the driver are how much force he is asking for, and where he is on the curve of force vs slip angle. He'd also like to know if the brakes are pulling. All the other stuff you get as steering wheel torque is noise, not information.


Perhaps adding to the pulling sensations, I'd include the effects of deep water. Not just the changes in the slip curve forces from aquaplaning, but the left/right difference in rolling resistance which results in a pull seems to aid in my wet driving.

EDIT: Greg, do you know the answers to my questions posed above about the potential lag in such a system? From sensors to any filtering to motor wind-up?

Edited by munks, 23 October 2012 - 14:56.


#241 Greg Locock

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Posted 24 October 2012 - 00:19

Perhaps adding to the pulling sensations, I'd include the effects of deep water. Not just the changes in the slip curve forces from aquaplaning, but the left/right difference in rolling resistance which results in a pull seems to aid in my wet driving.

EDIT: Greg, do you know the answers to my questions posed above about the potential lag in such a system? From sensors to any filtering to motor wind-up?

>OK, how about this: electrons or wireless signals can move faster (by wire or by air) than shock waves do through the steering system.

>That said, the steer-by-wire system presumably has sensor readings from the hub or steering link, from which they do some processing with the information, and then finally have to actuate a motor to provide feedback. I believe the last one would take the most time, but I don't know off-hand what the latency there might be.



yes, that is another signal that needs to get through, I'd forgotten that. Sorry missed those questions. The frequency response of a vehicle is a measure of the lag in the system, the output is a graph of yaw rate/SWA, vs frequency, and both the amplitude and the pahse of that graph are important. You will be not very amazed to learn I've measured this and the EPAS vs HPAS make no odds. At first sight that seems a bit odd since the inertia of the EPAS is pretty huge. They get around it by using a feedforward term, so if it knows it wants to move the rack by x mm in y ms, it adds enough extra torque to accelerate itself as well (which seems like cheating to this mechanical engineer).

Roughly speaking it takes a car about 100 ms to respond to an input from the steering wheel. You can reduce that by fitting better tires, stiffer wheels (debatable- subjectively it seems to help objectively not so much) or reducing the polar moment of the car, primarily. There is a neat bit of work in RCVD showing the build up of forces in the car as it starts to turn, I've done that in much greater detail, it is pretty interesting.

The main reason EPASs are currently on the nose is feel, and that is due to friction as much as anything. Again there is a table for friction suppression, so it adds enough extra oomph to overcome it, but if you go to far that way the system feels like it is motoring, which is very disconcerting. Should keep me in a job for years...

Edited by Greg Locock, 24 October 2012 - 01:20.


#242 gruntguru

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Posted 24 October 2012 - 02:03

How about some extra derivative or feedforward in the steer-by-wire system, to account for vehicle polar moment, tyre lateral compliance etc?

#243 Greg Locock

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Posted 24 October 2012 - 03:09

How about some extra derivative or feedforward in the steer-by-wire system, to account for vehicle polar moment, tyre lateral compliance etc?


Yes, you could come up with an ideal steering model for a car, and then use a combination of EPAS and ESC to make any car behave like that. The ideal would be BMW's column assist which can actually turn the steering wheel directly.

#244 gruntguru

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Posted 24 October 2012 - 03:25

Referring to true SBW systems, I imagine the transfer function would become pretty complex with P,I and D values (or equivalent) all dependent on vehicle speed and a range of other parameters. Perhaps it would be easier to rely on feedback from accelerometers etc so everything from variations in vehicle load to tyre pressures are compensated for. I suppose you then have a form of stability control?

#245 Greg Locock

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Posted 24 October 2012 - 05:26

Referring to true SBW systems, I imagine the transfer function would become pretty complex with P,I and D values (or equivalent) all dependent on vehicle speed and a range of other parameters. Perhaps it would be easier to rely on feedback from accelerometers etc so everything from variations in vehicle load to tyre pressures are compensated for. I suppose you then have a form of stability control?

The way the Bosch ESC system works is it has a little vehicle dynamics model in there, and it then assumes that the driver wants to drive the little model, and individually brakes the wheels on the real car to make it behave like the little model. So that is very close to what you are proposing I think. EPAS don't d that...yet. Yes every car with ESC has a yaw speed sensor of some form, whether it is a pair of accelerometers or just one MEMS chip I don't know.

#246 mariner

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Posted 24 October 2012 - 08:11

Greg, another question on your response measurements and artifical feedback? - you shouldnt have started this!

The grip levels of the front wheels are influenced by vertical tyre movement over bumps. So if the outside, loaded tire hits pothole the vertical force goes up then down so ( logically anyway) the self aligning torque will vary.

With a fully mechanical system that variation will be felt at the steering wheel rim. How does/will/cannot an artifical feedback system cope with vertical wheel movement varying lateral force capacity and self - aliging torque messaging to the driver.

With UK roads becoming very, very potholed such issues may be important to the English even if not the German OEM's who test on lovely smooth German roads!

PS my limited understanding is that some off road vehicles tend to have non-reversible steering sytems to actually limit such feedback aka the old Land Rover/Jeep

#247 Bloggsworth

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Posted 24 October 2012 - 08:36

Several interesting posts about how to, expensively, artificially achieve what the average driver takes care of without even thinking about it...

#248 Greg Locock

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Posted 24 October 2012 - 22:32

Several interesting posts about how to, expensively, artificially achieve what the average driver takes care of without even thinking about it...

Yes it is expensive and artificial. Now, given that manufacturing cars profitably is insanely difficult (I won't invest in it) why would we add hundreds of dollars to the price of a car if there weren't other advantages?

Mariner - The amount of kickback you get is a function of rack friction, rack reverse efficiency, and steering column compliance/damping/inertia/friction. There is a school of thought that say that friction is a bad thing, reverse efficiency should be high, and so on, and of course minimise on centre boost. That is brilliant for go karts, rubbish for driving long periods. Australian cars tend to have relatively low feedback, partly by running low scrub radius, but also a mixture of those other factors. That's because driving on gravel roads at 100 kph (ahem) would give you an insane level of feedback through the wheel.

"The grip levels of the front wheels are influenced by vertical tyre movement over bumps. So if the outside, loaded tire hits pothole the vertical force goes up then down so ( logically anyway) the self aligning torque will vary."

It certainly does

"With a fully mechanical system that variation will be felt at the steering wheel rim."

No, as explained above, even a mechanical system has adjustable levels of kickback, pinion angle being vital as it controls the reverse efficiency, and the pressure plate between the rack and housing being another. The latter is a pretty frightening parameter to play with as it affects how tightly the pinion meshes with the rack, and adds friction, and damping, all by turning one little screw.

" How does/will/cannot an artifical feedback system cope with vertical wheel movement varying lateral force capacity and self - aliging torque messaging to the driver."

Well for now we still have a direct connection, there isn't much between EPAS and HPAS in that regard. Drive by wire will need either force sensors in the tie rods, or yet another little model, which will sense the motor torque (current) and work out what the driver should be feeling to create that much torque. Then use a playstation steering wheel with force feedback.

"With UK roads becoming very, very potholed such issues may be important to the English even if not the German OEM's who test on lovely smooth German roads!"

Yet oddly the original X5 was a brilliant gravel road cruiser. Combining the refinement of big cars and the handiness of small cars is going to be a challenge for ever more.

Edited by Greg Locock, 24 October 2012 - 22:38.


#249 pugfan

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Posted 24 October 2012 - 22:33

Several interesting posts about how to, expensively, artificially achieve what the average driver takes care of without even thinking about it...


It is quite amazing how human drivers manage to achieve an accident rate of 0.

#250 Bloggsworth

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Posted 24 October 2012 - 22:53

No, as explained above, even a mechanical system has adjustable levels of kickback, pinion angle being vital as it controls the reverse efficiency, and the pressure plate between the rack and housing being another. The latter is a pretty frightening parameter to play with as it affects how tightly the pinion meshes with the rack, and adds friction, and damping, all by turning one little screw.

And remembering to lock it...