Run away cars

[trader4]

I never said nobody knows. I said YOU don't know how all cars that have been built in the last decade are built, so you shouldn't go around making blanket statements that just make you look foolish. Certainly the engineers that designed a particular car know.

Next time you talk with them, ask them how many computers are in a modern car. Is it one or two, like you claim, or dozens of them like the website dedicated to embedded computer engineering that I provided you with as a reference says? And while you're at it, ask them if the same computer that controls the airbags controls the climate system and the radio. Obviously you haven't been in any engineering development or you'd know how highly improbable that is. Despite claiming to know so much, you can't even grasp why.

Here's a clue. Who in their right mind would want a critical real- time system that has the capability of exploding airbags in your face co-mingled with the radio? And what exactly would be the purpose of building it the way you say with everything in one computer? First, it's unlikely that those components are even designed and/or built in the same place. More likely there are completely separate engineering teams, maybe one in Japan, another in Michigan, a third in Ohio. So why would they choose to share a computer and complicate things? With microcontrollers costing as little as $1, there is no reason to co-mingle all kinds of distinctly separate functions into one module. You put the computer close to where it's needed, segment the system logically, and have the computers talk to each other if needed.

Ever do any engineering change work or code validation? Somebody decides they need to fix a tiny bug in the radio or marketing wants to add a new feature. The fix involves changing the program code. If you have a $1 microcontroller functioning as the brains for the radio and entertainment system, you can make that change, validate it with regards to the radio and not worry that it COULD result in screwing up the airbag system, killing people. Do it the way you claim, and as soon as you change that program code for the radio, you have one hell of a big system validation problem covering not just the radio, but the critical airbags, climate control and God only knows what else because you decided to put it all together. There is a reason for modular design, ie breaking things up into logical units. And maybe I'm wrong. Maybe some cars do have the same computer that runs the airbags running the radio and climate control. But I'm betting you're wrong. Just like the mainframe gave way to PCs everywhere, with cheap microcontrollers and microprocessors, it makes sense in a car to do the computing where it's needed instead of in one central place. Just show us an example of a credible source that says the airbag, radio and climate control are done with the same computer.

[salty]

That is not an established fact.

[salty]

And there are no selenoids or hydraulic controllers on or in the transmission in addition to the mechanical shifter? Does the shift linkage itself perhaps have external stops controlled by selenoids?

[salty]

Completely irrelevant

[salty]

Unless it doesn't!

...or has some additional electronically controlled device to block it from moving under some conditions.

[snotty]

An awful lot can happen in 15 seconds. Especially at high speed on a busy road.

[Clot]

I had a minor nose to tail accident because I forgot that the vehicle I was driving had ABS.I am so used to cadence braking in urgent situations that it is now a problem for me.

These recalls make me ponder as to whether anyone driving today knows how their vehicle works?

[Ed Pawlowski]

wrote

I've never seen a transmission with a selenoid. Don't even know what one is. Not for neutral. Transmissions have lots of goodies that control shifting and take there information from the computer, but that is entirely different.

[Ed Pawlowski]

wrote

Do you have a list of those?

[clare]

In the first place - my statement about the number of "computers" in a car was in reguards to the operation of the powertrain, primarily - and I did also explain there are semantics involved. Depends what you want to call a computer.

At one point, cruise control was one computer, ABS was another computer, fuel injection was another computer, and ignition another one.sunroof was another computer, the automatic transmission was another,power windows was another computer, and if you had a driver information panel or a trip computer they were both separate - as was the compass and/or climate control. Digital dash was another computer. If it had electrically operated seat belt retractor locks that was another "computer" - then you added SRS (air bags) and automatic headlights

In todays cars, the fuel injection, ignition, transmission, cruise control, antilock brakes, traction control and even the voltage regulator are commonly all handled by one main computer, while climate control, driving computer, compass, doorlocks, sunroof, compass, instrument panel and seat belts, along with wipers and numerous other functions - in many cases even the RADIO. functions are controlled by another main computer.

The fact that microprocessors are also used in many of the "smart switches" that are built into things like BMW tail-light assemblies, door and window operators etc is not under dispute, but the definition of them as computers is playing pretty loose.

Calling the air bag computer control a computer IS accurate on some cars - on others all the operational smarts are in the sensors, while the "computer" is simply a monitor that makes sure there are no defects that would prevent the air-bags from functioning in case of an accident and turning on a light and storing a code when a malfunction is determined.

A string of switches that must all be turned to the right position to activate a circuit is not necessarilly a computer.

And even calling each "smart switch" on a BMW a computer, 100 is a big stretch....

'Nuff said.

It WILL happen. and in the not too distant future.

The bean counters will make sure it happens unless legislators get their panties into enough of a knot over this toyota BS that they pass a law to stop it.

Yes, I've done some. It's a royal pain.

Ever here of virtualization? It is happening in a big way in the computer industry - and you WILL see it in automotive computers, with one computer running numerous "virtual machine" processes on one processor , and each of those "virtual machines" handling different functions, with the code for each virtual machine and each function beng totally segmented and separately modifiable.

It all has to do with the integration and convergence, By eliminating all the separate $1 microcontrollers and "converging" all the different systems on one more powerfull CPU, there are MANY benefits that can be realized. Among them is easier fault detection and reporting, easier to implement redundancy, data verification and data sharing, and in the long run lower costs.

You will see more centralized design come back into automotive manufacturing as the complexity of today's cars increases. And the programming of these processes running on these virtual machines can still be done wherever you want it to be done - Bangalore, Karachi, Mumbai, Detroit, Singapore, Mexico, Milan, or wherever.

Modular design in the computer world does not have to mean separate physical computers. Opject Oriented Programming is modular program design, and re-useable programming building blocks can be assembled to control many different processes using the same basic code snippets, with separate data tables to modify the logic.

And today you are seeing a large movement back to centralized processing with client-server applications and "thin client" networks like Citrix because it is more effective and more secure to have the data and processes centralized. Just like "single entry" accounting systems, where all the data gets entered in one place, and is processed and manipulated and stored in one place. You see more relational databases where all the information required to run a business or produce a product is stored in a single data file on a single system - and possibly replicated to a second system for redundancy and capacity sharing.

This instead of a collection of numerous files, with different types of data stored in different files all over the storage device.

It is simply easier to control and verify data that is all in the same place.

Many cars have the radio, climate control, and door locks, window controls, compass, driving computer and instrument panel all on one computer, along with part of the airbag monitoring system.

While some vehicles use a real "computer" to control the airbags,the airbag control module in some cases is not a computer at all. Simple boolean logic (and, or, not, nand etc gates) is all that is required. The module gets signals from the main (Powertrain control or body control) computer saying the conditions (speed etc) are right to enable the supplementary restraint system, and if a front impact (inertia) sensor gets tripped, it sets off the front air bags. If a rollover sensor or side impact sensor gets actuated, it sets off the side curtain airbags. No programming or computational ability is required, so it is not a computer. It is just a couple of electronic switches.

[clare]

Where there is a mechanical linkage, it IS a fact. Working properly or not..

[clare]

The electrical solenoids control fluid flow to actuators in a transmission, but the manual valve controls the supply of fluid under pressure to the solenoids. The only solenoids generally acting on the shift linkage are the park/brake interlocks that prevent the transmission shifting out of park without the brake being depressed. Park is at the end of the range of motion of the manual linkage, so shifting into or out of neutral is not affected.

[clare]

You are saying such a device exists. You prove it. Heck of a lot easier to prove something exists tha to prove it doesn't.

Show me.

[salty]

It might help if you at least knew what a selenoid was, and some of the things it can do when signaled ELECTRONICALLY. In your post above, you acknowlege they are there but don't understand them. It's thsoe "goodies".

[salty]

I think the technical term I saw a guy on usenet call them was "goodies"

[salty]

Thus proving conclusively that you don't even know the basics of what constitutes a computer.

[Ed Pawlowski]

wrote in

So, you say it is something like a SOLENOID? I know what they are

[salty]

Sorry, but you are 100% wrong. Do you understand the concept of a deadbolt on a door preventing it from opening no matter how much you twist and pull the mechanical door knob mechanism which is completely separate from the deadbolt, but normally would allow the door to open?

[trader4]

Uh huh. And you're so knowledgable about all the various Toyota models that you can state that for sure there isn't even a slim possibility that one of those interlocks is couldn't malfunction under conditions of either

A - the computer running amock

B - the car is under full throttle acceleration

You'd testify to that in court? You're the guy who says modern cars have only two computers and some have only one. We're still waiting for a single reference to support that nonsense. Or should we reserve final judgement until all these cars are looked at by engineers who understand the design and what controls what. Ever see the NTSB rush to pass judgement on a plane crash before a full team consisting of representatives of the manufacturer, engine maker, avionics maker, and the NTSB itself has had a year or more to analyze and make sure what really happened?

Maybe you're not aware of it, but some cars today can PARK THEMSELVES at the curb. Clearly that involves shifting the transmission in and out of drive while applying the accelerator. I suppose you're an expert on how that system works too.

[trader4]

On Mar 14, 1:17=A0am, [e-mail] wrote: quoted text -

More BS. You stated that most new cars had one computer for the engine, one for the body and some cars had only one.

I'll go with the definition used by the website for engineers who design embedded computer systems, because that's what these computers are.

And they say any modern car has dozens of computers. You on the other hand told us that you can use a microprocessor in a way that it is not in fact a computer, which is ridiculous, unless you're using it for a doorstop.

BS. There are lots of microprocessors in cars doing more than being a smart switch. I could implement a smart switch with a simpler design using a sequential state machine.

Hmmm, I remember you telling us that the airbag function, the climate control, and the radio were all in one computer. Now you're backing away from that. But what we have above is still ridiculous. Explain how you have "smarts" in sensors or anything else without there being a computer? It may be a $1 microcontroller, but it is a computer. Perhaps you've missed the news. Want me to go find you more stories that say your home is full of computers today besides the one on your desk? Like the typical DVD player, microwave, fancy washing machine, dishwasher, telephone, cell phone, etc. They are all implemented using microprocessors or microcontrollers.

No but anything containing a microprocessor or microcontroller is. Hence the stories that say cars today are chocked full of them. Where is your story that says cars only have one or two? And what is the big driving force for this computer centralization? It would be like going back to the days of the mainframe, instead of a distributed computing architecture.

Yes, enough said. The people who made that supposedly outrageous claim are just engineers who design embedded computer systems.

Ohh. Stop the presses. In the other thread you made the claim that it existed today and you knew it for sure. Now it's a coming attraction.

Obviously it's you who is the bean counter. Because if you were involved in actual engineering design, you'd know that the cost of a cheap microcontroller pales in comparison to the engineering and development effort, system simplification via logical segmentation, etc.

Then surely you are an idiot, because anyone that has knows that when you partition a system in some logical fashion development is faster, easier, less costly, easier to maintain, etc. Yet, your here arguing that there is one computer controlling the airbags, the climate control, and the radio. To what purpose? Take the radio. It surely already has an electronics board containing the tuner, human interface, etc. Why the hell would you not put a $1 microcontroller in there to run it and instead rely on a computer somewhere else? Putting it in the radio, you now have a fully functioning subsystem that you can work with. Do it the way you claim, and you have to rely on some computer being developed God knows where.

I see you have no answer to that one

Sure, just like were going to go back to the days of the mainframe.

You really are lost here in the wilderness. How the hell does one powerfull CPU implement redundancy? In fact, it's exactly the opposite because you have NO redundancy. How does it make fault detection easier? I don't know about you, but I don't want the computer that is controlling the airbag detonation to be co-mingled with a bunch of other crap like the radio.

Please provide a single reference to back this up. How is the team going to design the radio in Korea while the CPU for the thing is being designed in Detroit? Yeah, it could be done, but anyone with a lick of experience knows that it isn't done that way. You put a cheap microprocessor or microcontroller on the board already in the radio and then you have a self-contained functioning subsystem. Your way, you save what? Nothing. You've made the design more complex. You've made the development FAR more complex. And all you've accomplished is to replace a $1 microcontroller with part of a computer somewhere else that has to be MORE powerfull and hence costs more. You haven't saved a thing. Which is why the trends are exactly the opposite of what you claim, ie there are more computers going into cars each year, not less.

BS. You put that radio code into the same computer that controls the airbag and I don't care how you try to segment it, one thing can effect the other. Hence, now to make any change to one function, you have to revalidate the entire thing, especially when the computer can detonate the airbags. PCs use all kinds of advanced modular techniques too. Would you rely on yours to control the airbags while also running God knows what?

Client/server is a classic example of distributed computing. Geez, what percentage of the computing power today is mainframe versus 30 years ago? I've provided you plenty of links that say the number of computers in cars today is dozens and increasing. Just provide us with a link that says there are only one or two and that the trend is to centralize the computing into one CPU. Link please.