electronic throttle
in [Technical]
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From: jim beam on 6 Mar 2010 10:30 if you buy all this fear-mongering idiocy that electronic throttle is a problem, and that brakes, transmissions and ignition kill switches can all simultaneously fail causing a driver to lose control, it might be worth auto manufacturers of all stripes to adopt a slightly different implementation of electronic throttle [e.t.] - if not for mechanical reasons, but to shut the idiots up. first, lets understand e.t. functionality: 1. open the throttle when demanded 2. close throttle when demanded 3. allow "demand" to account for additional requirements like a. de-throttle on shifting for automatics, b. throttle appropriate to load at high demand [eg. full throttle at low rpms can choke an engine and significantly reduce output - thus de-throttle until revs support full open] if we analyze the above [which is not exhaustive, but representative], we find that in almost all situations, an e.t. needs to be more closed than demanded, but seldom, if ever, more open. thus the "solution" to the fear-mongering might be to have the throttle opened mechanically - i.e. old fashioned cable linkage, but have the computer control a closer device. thus, all the above can be implemented electronically, but whenever the driver lifts their foot, the mechanical closure cannot be over-ridden. and the throttle can never be more open than the mechanical throttle command. this would not only address the "potential" for a runaway failure [although how exactly a computer is supposed to fail such that it won't switch off, disables brakes, disables transmission select, but still runs its injection code is something i have never seen explained, even by the most strident "but it must be the electronics" crowd], but it would also remove the single most annoying thing i have ever experienced in any vehicle driving experience: chevy's idiot idea that they need a multi-second delay between foot pedal movement and e.t movement. anyone that's ever tried to drive a chevy hhr on a winding mountain road knows what i mean. y'all can now wait for at least 10 years for arrival, but i throw it out there for what it's worth. -- nomina rutrum rutrum
From: Bill Putney on 6 Mar 2010 10:38 jim beam wrote: > if you buy all this fear-mongering idiocy that electronic throttle is a > problem, and that brakes, transmissions and ignition kill switches can > all simultaneously fail causing a driver to lose control, it might be > worth auto manufacturers of all stripes to adopt a slightly different > implementation of electronic throttle [e.t.] - if not for mechanical > reasons, but to shut the idiots up... The lawyers, politicians, and news media can convince the public of the impossible (failure even a totally fail safe system) any time they decide to do it depending on political or monetary motivation. IOW - the people and companies who do a good job of designing are going to get punished anyway (unless they know how to play the game in a corrupt system). There are people in our society whose life goal is to make sure that that happens. -- Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
From: jim beam on 6 Mar 2010 10:48 On 03/06/2010 07:38 AM, Bill Putney wrote: > jim beam wrote: >> if you buy all this fear-mongering idiocy that electronic throttle is >> a problem, and that brakes, transmissions and ignition kill switches >> can all simultaneously fail causing a driver to lose control, it might >> be worth auto manufacturers of all stripes to adopt a slightly >> different implementation of electronic throttle [e.t.] - if not for >> mechanical reasons, but to shut the idiots up... > > The lawyers, politicians, and news media can convince the public of the > impossible (failure even a totally fail safe system) any time they > decide to do it depending on political or monetary motivation. IOW - the > people and companies who do a good job of designing are going to get > punished anyway (unless they know how to play the game in a corrupt > system). There are people in our society whose life goal is to make sure > that that happens. > indeed. but given that, unlike ignorance, there's no cure for stupidity, and that vehicle manufacturers have to be smart about politics, not just engineering, i've been thinking the above is one of those solutions both mechanically and politically acceptable. -- nomina rutrum rutrum
From: Paul on 6 Mar 2010 10:53 Cable !!!! That is soooo 1990's. Reminds me of my old Pontiac. Cable opened the throttle plate and computer controlled the amount of fuel injected. jim beam wrote: > than demanded, but seldom, if ever, more open. thus the "solution" to > the fear-mongering might be to have the throttle opened mechanically - > i.e. old fashioned cable linkage, but have the computer control a closer > device. thus, all the above can be implemented electronically, but > whenever the driver lifts their foot, the mechanical closure cannot be > over-ridden. and the throttle can never be more open than the > mechanical throttle command.
From: Jeff Strickland on 6 Mar 2010 11:36
"jim beam" <me(a)privacy.net> wrote in message news:fvudnV-hwr-Z6A_WnZ2dnUVZ_rednZ2d(a)speakeasy.net... > if you buy all this fear-mongering idiocy that electronic throttle is a > problem, and that brakes, transmissions and ignition kill switches can all > simultaneously fail causing a driver to lose control, it might be worth > auto manufacturers of all stripes to adopt a slightly different > implementation of electronic throttle [e.t.] - if not for mechanical > reasons, but to shut the idiots up. > > first, lets understand e.t. functionality: > > 1. open the throttle when demanded > 2. close throttle when demanded > 3. allow "demand" to account for additional requirements like > a. de-throttle on shifting for automatics, > b. throttle appropriate to load at high demand [eg. full throttle at low > rpms can choke an engine and significantly reduce output - thus > de-throttle until revs support full open] > > if we analyze the above [which is not exhaustive, but representative], we > find that in almost all situations, an e.t. needs to be more closed than > demanded, but seldom, if ever, more open. thus the "solution" to the > fear-mongering might be to have the throttle opened mechanically - i.e. > old fashioned cable linkage, but have the computer control a closer > device. <snip rest> Nothing you say after this makes any sense. If you have a mechanical opening device -- cable for example -- then it is by definition closed with another mechanical device -- a spring. The whole point of e.t. is to remove the constraints that surround mechanical linkage of the gas pedal to the throttle plate. If you are not going to remove the constraints of a mechanical system by employing it for the opening of the throttle, then you can use the return spring that any mechanical method would require to return the mechanism to the home position. The same spring that brings the gas pedal to home can also bring the throttle to home. |