[asethi]

Originally Posted by im_srini

The Swift diesel comes with an electronic throttle, by extension, cars from other stables that use the multi-jet-diesel engine should come with electronic throttles too.

Ok, so now I got it! Sometimes when my SwiftD isn't pulling even though the accelerator is pressed almost all the way down (especially while starting from still), I just release the accelerator and just press it lightly again and the car then pulls normally!

[profold]

Originally Posted by ajaysurfs

Thanks Profold.

When i was Germany few years back, one of my colleagues (who was physically challenged) used to drive a retrofitted Golf (Automatic). Steering was as usual as with other cars (with a kind of blob for easy maneuverability), however there was a kind of joystick in pace of gear lever - when pushed forward the car used to accelerate and when pulled back it used to brake. There were no pedals to be seen.

So i think in similar circumstances DBW becomes indespensable.

Thanks again, ajaysurfs
Yes, X-by-wire applications have arrived in vehicles for the physically challenged and to good effect. Another area is ultra slow speed vehicles within airport, golf carts and likes.
The manual brake in electric vehicle, really is a fall back, as much of the braking is performed electrically to recover energy.


I understand that there are many research vehicles with steer-by-wire technology. I do not think these ever got the road worthiness certificate.

Cheers.

[profold]

Originally Posted by asethi

Ok, so now I got it! Sometimes when my SwiftD isn't pulling even though the accelerator is pressed almost all the way down (especially while starting from still), I just release the accelerator and just press it lightly again and the car then pulls normally!

Believe that this is not due to throttle by wire, the Engine ECU may be programmed that way. Even with manual throttle, the Engine ECU may perform similarly. That is by pressing the pedal, only more air is allowed to the chamber. The ECU decides how much fuel to inject.

[frankmehta]

The Fiesta too, comes with DBW for the accelerator. I guess the instantaneous response of the engine to the slightest of dabs could be attributed to that in a way.

[ImmortalZ]

Originally Posted by profold

Believe that this is not due to throttle by wire, the Engine ECU may be programmed that way. Even with manual throttle, the Engine ECU may perform similarly. That is by pressing the pedal, only more air is allowed to the chamber. The ECU decides how much fuel to inject.

Diesel engines do not have a throttle.

[amitk26]

EPS or electrical power steering in cars from Maruti stable is an example of Steer by wire but often criticized for over steering.
Other kind of power steering more commonly found use hydraulics based power steering deriving power from engine using belts.

[VeeTee]

Originally Posted by ImmortalZ

Diesel engines do not have a throttle.

Throttle also refers to the accelerator pedal. I don't think he is refering to the throttle body in this case.

Any vehicle with an ECU, is essentially drive-by-wire since accelerator pedal is one of the inputs to the ECU (actually one of the main inputs)

Satish

[ImmortalZ]

In a sense, yeah. Earlier you used to control the throttle body butterfly with your pedal, connected by cable and the ECU used to know how much pedal you were giving with a throttle position sensor in there. Now the ECU controls the throttle body and the sensor now resides in the accelerator pedal.

Can't help but think the earlier system was better for driving cuz every DBW car these days has an annoying lag in throttle response. Even BMW have admitted to this and they haven't been very successful in reducing it. All in the name of emissions. Phtooey!

[profold]

Originally Posted by asethi

Ok, so now I got it! Sometimes when my SwiftD isn't pulling even though the accelerator is pressed almost all the way down (especially while starting from still), I just release the accelerator and just press it lightly again and the car then pulls normally!

For an explanation of what may happen (ECU reset !!) if the accelerator pedal is pressed all the way down, under certain conditions, please look up the thread " SX4 : Throttle Body Adjustment on drive by wire ", initiated by ITNerd. This thread also contains interesting discussions on drive by wire (or shall I say "throttle by wire"?).

Originally Posted by amitk26

EPS or electrical power steering in cars from Maruti stable is an example of Steer by wire but often criticized for over steering.
Other kind of power steering more commonly found use hydraulics based power steering deriving power from engine using belts.

IMHO, Power Steering is really "power assist" . It is not 100% steer by wire, as the road wheel angle is determined by the steering wheel position as set manually. The power assist amplifies the muscle power by hydraulic or electric means. In higher speeds, I understand, many power steering systems gracefully make way for the muscle.

Originally Posted by VeeTee

Throttle also refers to the accelerator pedal. I don't think he is refering to the throttle body in this case.
Satish

Yessir. Thanks for the clarification. In automotive context, the throttle always means the mechanism to control airflow. The accelerator pedal (though often referred as "gas" pedal) does always control the airflow.
(In aircraft though, the throttle, once upon a time, used to control the fuel directly.)

Originally Posted by VeeTee

Any vehicle with an ECU, is essentially drive-by-wire since accelerator pedal is one of the inputs to the ECU (actually one of the main inputs)

Satish

Nosir, beg to differ. It appears that the accepted usage of "Drive-by-wire" encompasses all sorts of X-by-Wire technologies, including brake-by-wire, steer-by-wire etc.(I do not like this but that is what Wikipedia and other sources insist). I therefore chose the term "throttle by wire" where there is no mechanical linkage between the accelerator pedal and the throttle mechanism.

P.S. As a support to the above comment about "Drive-by-wire" , I would like to cite Rehaan's post dated 8th February 2009, in the thread "NHC drive by wire". I honestly consider Rehaan to be an authority.

[sudipt123]

The Chevy Spark has DBW- Gm use the acronym - MTIS (motorised throttle intake system) for the accelerator . Some people have reported that the pedal comes "alive" on the forum. However no problems experienced by me.

[ph03n!x]

The clutch would tend to stiffen up over time, and driving a hard clutch in traffic can be a pain. An electric motor doing the job would be oh-so-great.

So, my question is - are there any cars that offer a drive-by-wire kind of implementation for clutches too?

[pranavt]

Yeah, they're called automatics

[ph03n!x]

Originally Posted by pranavt

Yeah, they're called automatics

But that is not what I meant - a good, ol' stick shifter WITH a clutch, but driven by motor. All I could find through google is this paddle clutch actuator.

[freewheelburnin]

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.

[ph03n!x]

Originally Posted by freewheelburnin

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?

That's the first time I heard about a motor driven gear shifter - I have heard of cable connected gearshift, but not this. A bit of googling threw up Ford Duroshift, that is recently launched for manuals also.