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Old 27th January 2011, 17:40   #31
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Default Re: Drive by Wire Technology

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Originally Posted by freewheelburnin View Post
I would like to add that recently i had access to the service manual of fiesta.A friend had purchased it from Ford(International website for same engine).I saw that the gearshifter was actually just an electronic controller though the clutch was manual.There was a motor connected to gearbox which would do the actual gearshift.
I doubt so. Fiesta owners, please confirm.

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Originally Posted by freewheelburnin View Post
I personally would not like a wire to control something as critical as a steering or a brake.Electronic systems are more prone to random and unexpected behavior.Also you would not get the slightest clue till something fails.Imagine a rat just chewed off your brake wire!Mechanical systems or electro mechanical systems are more robust.The counter argument could be the use of advanced diagnostic mechanisms.But even these are not fool proof either.
Well, all critical systems which affect safety are infact fail safe. It will work whatsoever, but with reduced efficiency.

Take for example, EPS. Even if the Electronic module fails, the car will steer, but it would take a lot more effort. Same case with power brakes, ABS etc.

You would get enough time to get back to the safety of A.S.S.

Another example is that, in my IKON, if the Engine Coolant sensor goes kaput, the engine wont start, let alone overheat. In other cars, the fan always runs in high speed to ensure the engine is not overheating.
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Old 28th January 2011, 07:52   #32
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Originally Posted by dhanushs View Post
I doubt so. Fiesta owners, please confirm.
@dhanush,

Thats correct, Fiesta has Drive by wire technology. Thats the reason for the shorter gear shifts.
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Old 28th January 2011, 11:52   #33
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Default Re: Drive by Wire Technology

Quote:
Originally Posted by freewheelburnin View Post
... I saw that the gearshifter was actually just an electronic controller though the clutch was manual. ...
Quote:
Originally Posted by dhanushs View Post
I doubt so. Fiesta owners, please confirm. ...
So do I! Service Manuals cover more than one model of a car, and different models may have different complements of equipment. So, while reading one has to be careful to read w.r.t. the specific car model that one is looking at (physically), and not use conjecture to infer that if the manual contains some information, the car WILL have the equipment mentioned in the manual.

* Most autoboxes today have motorized shifting, controlled by the transmission ECU. If there was indeed a clutch, the tranny was not an autobox
* Any extra electronics is additional cost. To keep costs down for India, car makers avoid adding unnecessary sophistication. If autobox is not necessary, Ford will not use a higher cost transmission with electronic control

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Originally Posted by dhanushs View Post
Well, all critical systems which affect safety are infact fail safe. It will work whatsoever, but with reduced efficiency. ...
Absolutely correct. Even the few joystick driven cars that were built for differently abled people didn't discard the conventional controls - the DBW systems were simply added on.

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Originally Posted by ghodlur View Post
... Thats correct, Fiesta has Drive by wire technology. Thats the reason for the shorter gear shifts.
Errrr... how did you infer this? What has DBW got to do with shorter gear shifts?
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Old 28th January 2011, 13:13   #34
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Default Re: Drive by Wire Technology

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Originally Posted by esteem_lover View Post
I have literally rode my Yezdi by wire many times when the accelerator cable gets cut. Have to hold the wire & pull to accelerate and push to decelerate.
fantastic!! This is literally drive by wire technology that we have been used to, during the good old days of TVS 50's and champs

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Originally Posted by DerAlte View Post
So do I! Service Manuals cover more than one model of a car, and different models may have different complements of equipment. So, while reading one has to be careful to read w.r.t. the specific car model that one is looking at (physically), and not use conjecture to infer that if the manual contains some information, the car WILL have the equipment mentioned in the manual.

* Most autoboxes today have motorized shifting, controlled by the transmission ECU. If there was indeed a clutch, the tranny was not an autobox
* Any extra electronics is additional cost. To keep costs down for India, car makers avoid adding unnecessary sophistication. If autobox is not necessary, Ford will not use a higher cost transmission with electronic control

Absolutely correct. Even the few joystick driven cars that were built for differently abled people didn't discard the conventional controls - the DBW systems were simply added on.

Errrr... how did you infer this? What has DBW got to do with shorter gear shifts?
I guess he means quicker and precise shifts.

Well, correct me if iam wrong, the DSG(Dopple-Kupplungs-Getriebe) dual clutch transmission works in a way by preparing the subsequent gear once a gear is slotted in and this is done by a electric motor to keep the gear in ready to engage position powered by the second clutch. For eg. a DSG has seperate clutch for odd numbered gears and a seperate one for even numbered ones, so if we engage 1st then 2nd gear would have already been prepared for engagement and when we slot the lever or the the paddle the ECU would send a pulse to the motor to engage the gear 2 and prepare the 3rd gear for engagement.

Also, I have question, the old automatics, how did they work? did they had any mechanical sources to indicate the speed and automatically engage, because I believe during the early days of automatics, the technology was not so advanced to see the light of advanced electronic gizmos doing the job instead of sturdy mechanical ones!!
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Old 28th January 2011, 13:34   #35
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Originally Posted by DerAlte View Post
Errrr... how did you infer this? What has DBW got to do with shorter gear shifts?
Although technically I would not be able to tell you what DBW has to do with shorter gear shifts but I distinctly remember the explanation given by the Ford SA when I was taking the test drive when I found the gear throws to be smaller than my earlier Santro. The SA had told me specifically that the usual manual clutch assy is replaced by a motorized operation in Fiesta, hence the short gear throws.

Maybe Alphakilo's explanation holds true for the above.
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Old 28th January 2011, 19:45   #36
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Default Re: Drive by Wire Technology

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Originally Posted by AlphaKilo View Post
... I guess he means quicker and precise shifts.

... the DSG(Dopple-Kupplungs-Getriebe) ...
DSG is a completely different ballgame, and would do short throws even if the engine was carburetted or had inline-pump injection (i.e. without ECU).

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Originally Posted by AlphaKilo View Post
... the old automatics, how did they work? ...
Hydraulic actuators! Easy to figure out speed from the pressure generated by the pump. Calibrate the control mechanism based on that.

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Originally Posted by ghodlur View Post
... I distinctly remember the explanation given by the Ford SA when I was taking the test drive when I found the gear throws to be smaller than my earlier Santro. The SA had told me specifically that the usual manual clutch assy is replaced by a motorized operation in Fiesta, hence the short gear throws. ...
SA = Sales Advisor or SA = Service Advisor? To me it looks like it was the Sales Advisor. Just like a Hyundai Sales Advisor had told me about 10 years back while I was looking at a Accent Tornado GTX: "Sir, the gear knob in this car is the same as in Tiburon, that's why it runs like a sports car"! Well, I bought the car, but not for the explanation he gave me.
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Old 29th January 2011, 04:56   #37
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Default Re: Drive by Wire Technology

Quote:
Originally Posted by freewheelburnin View Post
I would like to add that recently i had access to the service manual of fiesta.A friend had purchased it from Ford(International website for same engine).I saw that the gearshifter was actually just an electronic controller though the clutch was manual.There was a motor connected to gearbox which would do the actual gearshift.Can any fiesta owners confirm this?
I strongly suspect your friend's manual has info about Ford's Durashift EST Transmission.

"A Transmission Control Unit (TCU) is integrated into the clutch actuator. The TCU gives commands to electric motors that control the shift and select mechanisms in the gearbox and the electric motor in the clutch actuator itself, which operates the hydraulic line for the clutch release system.


Three small electric motors take the place of the clutch pedal and the cables normally required by the clutch and shifting mechanism. Two of these motors do the shifting work for the driver, and the third motor, supported by a strong spring, actuates the clutch. This arrangement simplifies the driver's tasks and contributes to more economical vehicle operation."

Source: Ford Forums

The Indian Fiesta does not come with this.

Quote:
Originally Posted by ghodlur View Post
Thats correct, Fiesta has Drive by wire technology. That's the reason for the shorter gear shifts.
Even if we assume that the Fiesta does have a DBW shifter, that doesn't really mean the shifts would be shorter, and vice versa, ie , if sensibly designed, a manual shifter can be short, slick and fun.


Quote:
Originally Posted by DerAlte View Post
Just like a Hyundai Sales Advisor had told me about 10 years back while I was looking at a Accent Tornado GTX: "Sir, the gear knob in this car is the same as in Tiburon, that's why it runs like a sports car"! Well, I bought the car, but not for the explanation he gave me.
There is an entire thread dedicated to the intellect of these SA's .

Last edited by dhanushs : 29th January 2011 at 04:59.
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Old 29th January 2011, 10:23   #38
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Originally Posted by DerAlte View Post
SA = Sales Advisor or SA = Service Advisor? To me it looks like it was the Sales Advisor. Well, I bought the car, but not for the explanation he gave me.
It was Sales advisor who had given that explanation. I too did not buy the car based on the explanation given by the sales guy but purely on the test drive feeling. The gear shifts were too smooth and quick too. Thats the time when I asked the SA about the gear mechanism. As long as I am satisfied with the gear shift performnace I am not too bothered whether its DBW or not.
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Old 29th January 2011, 11:10   #39
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Default Re: Drive by Wire Technology

Quote:
Originally Posted by freewheelburnin View Post
I would like to add that recently i had access to the service manual of fiesta.A friend had purchased it from Ford(International website for same engine).I saw that the gearshifter was actually just an electronic controller though the clutch was manual.There was a motor connected to gearbox which would do the actual gearshift.Can any fiesta owners confirm this?
I personally would not like a wire to control something as critical as a steering or a brake.Electronic systems are more prone to random and unexpected behavior.Also you would not get the slightest clue till something fails.Imagine a rat just chewed off your brake wire!Mechanical systems or electro mechanical systems are more robust.The counter argument could be the use of advanced diagnostic mechanisms.But even these are not fool proof either.
DBw
No fiesta in india doesnot come with DbW tech in gear shift.

Infact in india the DbW is implemented only in accelerators as of now.

most of the people got the concept wrong,it is not just the electronic throttle which mean DbW tech and swift does not have DbW yet.

Actually Dbw will replace the cables with sensors ,where as even now swift comes with cable which in turn triggers the ECU in the engine compartment.if it was dbw it would not have cable.

DbW has been implemented in steering in few cars abroad,ie..it is like the video game where you turn the wheel and in the video your car turns.No Mechanical parts connects the steering wheel and steering box !

As of now i heard apart from Merc,bmw audi ect .. scorpio has DBW tech for accelerator
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Old 29th January 2011, 15:38   #40
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Default Re: Drive by Wire Technology

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... swift comes with cable which in turn triggers the ECU in the engine compartment ...
The accelerator cable is connected to the ECU is Swift? What does it trigger in the ECU?

Other than throttle body / manifold injectors of yore (one injector for all cylinders! Not sure if any car in India has that any longer), any car with 1 injector per cylinder, controlled by ECU, has a sensor at the acc pedal which the ECU reads to know 'driver demand'. That is DBW.
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Old 30th January 2011, 00:09   #41
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Default Re: Drive by Wire Technology

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Originally Posted by DerAlte View Post
DSG is a completely different ballgame, and would do short throws even if the engine was carburetted or had inline-pump injection (i.e. without ECU).

Hydraulic actuators! Easy to figure out speed from the pressure generated by the pump. Calibrate the control mechanism based on that.

SA = Sales Advisor or SA = Service Advisor? To me it looks like it was the Sales Advisor. Just like a Hyundai Sales Advisor had told me about 10 years back while I was looking at a Accent Tornado GTX: "Sir, the gear knob in this car is the same as in Tiburon, that's why it runs like a sports car"! Well, I bought the car, but not for the explanation he gave me.
Quote:
Originally Posted by DerAlte View Post
The accelerator cable is connected to the ECU is Swift? What does it trigger in the ECU?

Other than throttle body / manifold injectors of yore (one injector for all cylinders! Not sure if any car in India has that any longer), any car with 1 injector per cylinder, controlled by ECU, has a sensor at the acc pedal which the ECU reads to know 'driver demand'. That is DBW.
Herr. DerAlte danke!! Hail all auto enthusiasts on this 125 year of automobiling, especially to all TBHPians. Thank you for the correction and info on old Auto boxes. Gear knob like Tiburon and you bought the car based on that? On the lines of our Dear Sam Kapasi, "gear knob like in tiburon, paisa vasool" On the other hand, may be little OT, but even the bike manufacturers tend to call them Throttle positioning system controlled by a cable like YTPS and Suzuki TPS. And I understand from the above posts that Swift has something similar to the bikes. But I did a check on swift DZire, DDIS acc pedal, i didnt find any cable rather found a sensor on the point where the top edge of the pedal will touch the ground if fully pressed and a simple spring system to pull the pedal back to zero position once the foot pressure is released from it.
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Old 30th January 2011, 10:04   #42
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Default Re: Drive by Wire Technology

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Originally Posted by AlphaKilo View Post
... Gear knob like Tiburon and you bought the car based on that? ...
Throttle positioning system controlled by a cable ...
i didnt find any cable rather found a sensor on the point where the top edge of the pedal will touch the ground ...
LOL Noooo I bought the Accent GTX because of the peppy 1.6L engine and great handling, not because of the Tiburon gear knob! At that time, Ford Ikon and Accent GTX (with a Kenwood HU, components in front, ABS, power windows and a spoiler) were the only 2 capable cars in that segment, though most people preferred the Ikon or the more staid and plain Accent. Lancer was a costlier option.

Throttle Positioning System is the technically correct name, though they made it sound esoteric since the others didn't talk about it. The Throttle (either the butterfly valve or the cylindrical sleeve in the carburettor) 'throttles' (chokes) air going into the cylinder(s), and the TPS 'positions' it based on how fast the driver / rider wants to go (how much air flow the cylinder needs to run as fast as the driver/rider wants).

That sensor attached to the gas pedal is a simple potentiometer (or sometimes 2 for redundancy) similar to the volume control in 2-in-1s which have stops at either end (not continuously rotatable). The shaft of the potentiometer rotates as one presses the pedal, and the ECU reads the resistance of the pot as the pedal position or 'driver demand'.

Last edited by DerAlte : 30th January 2011 at 10:06.
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Old 30th January 2011, 12:44   #43
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Default Re: Drive by Wire Technology

The potentiometric sensors reminds me of one thing, the new ALL buses have such a system manufactured by Williams controls(or atleast thats what the pedals in the buses are marked) and I remember reading an explanation for the same in the heavy vehicles thread by Ashley(if i remember it correctly).

IMHO, I feel its nice to have a little bit of mechanical touch to such critical systems, so that even a road side mechanic would be able to work on it, if need arises, and even though they are made "Fail Safe", it gives an artificial feel and takes out the whole pleasure of manual driving.

Such an opinion not only prevails in the auto industry but even amongst Pilots who fly the worlds biggest three wheelers. Airbus series are dubbed as computer aircrafts and Boeings are pilot friendly manual ones. Its just individual perception for electronics. Oops going OT.
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Old 30th January 2011, 21:06   #44
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Default Re: Drive by Wire Technology

IMHO, "roadside mechanics" will not have too much to do in the world of modern vehicles, unless they get re-educated compulsorily. The keys to not facing an uncertain circumstances on the road are:
* One has to keep the vehicle ship-shape with appropriately frequent servicing, and not wait for a failure to happen (Murphy's law notwithstanding)
* Manufacturers & independent service organizations must gear up far & wide convenient service availability, including converting self-taught roadside mechanics to educated mechanics. Maruti, for example, has done it and touts it as it's USP. It is not just a matter of investment - it creates a whole new eco-sphere. That is not too far away in future

High degree of automation or manual is not the issue - the issue is of convenient service availability if something does go wrong.
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Old 30th January 2011, 23:27   #45
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well i stumbled up on this revived thread and read the above postings.Few points from my side even though they could have been posted.Generally most of the cars are now x-by-wire , where in replace "x" by Steer , Brake , throttle ,shift etc. The mentioned mechanical parts are directly connected to ECM / BCM / PCM / other Controll modules via sensors and they inturn control the required action.The classic example would be Electronic Throttle Control where in as mentioned above the accelerator pedal in swift is connect to EnginControlModule which evaluates driver request and calculates the actual torque required by considering the losses and command the throttle plate to open up certain percantage.simultaneously the injection , ignition timing are also calculated in the ECM and sent to the powerstages which control the injectors , ignitors. in shift by wire , ex paddle shifts the user just taps the gear shift and the actual gear engaging is achieved using TCM/PCM.Ford uses Dual clutch system in the latest cars ( not aware if this is carried to indian model ) where the next gear is already engaged when you are driving in one gear so the gear shift timings are extremely low !!. so if you are driving in 2nd gear the 3rd gear is already engaged and just needs to be locked to the shaft.
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