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> In both cases - aircraft and cars - the primary goal was reducing weight. That wikipedia article is a lot of unsourced nonsense written by complete idiots wh
by KennyBlanken 5y ago
> In both cases - aircraft and cars - the primary goal was reducing weight.
That wikipedia article is a lot of unsourced nonsense written by complete idiots who clearly lack subject-area knowledge
The goal for drive-by-wire in cars was primarily emissions reduction. Many cars "smooth" throttle inputs to improve mileage and emissions. In some cars "eco" mode exaggerates that smoothing, or changes the mapping of the throttle to allow for much more control over a lower portion of the throttle range. In others, "drive" is smoothed, and "sport" mode is not (unfortunately "sport" mode often makes the transmission far too aggressive.)
It brings mechanical simplicity, because cruise control can be integrated in.
Drive by wire throttles were notoriously unreliable for almost a decade after their introduction. They get gummed up, the actuators fail, the position sensors fail, etc. It's a laugh that the article claims they're "easier to service" - they're usually buried in difficult-to-access places and there's nothing "serviceable" about them compared to a true mechanical throttle that can usually be completely rebuilt.
- jacquesm 5y agoCorrect. The whole idea was to decouple the accelerator pedal from the throttle using a sensor, a computer and an actuator to ensure that the right amount of fuel/air would be passed into the engine. https://en.wikipedia.org/wiki/Stoichiometry https://en.wikipedia.org/wiki/Stoichiometry If you don't do that then the excess fuel goes back out unburned. Multi point injection has changed this process a bit in that compared to the first single point injection systems the fuel is mixed with the air on a per-cylinder basis leading to better fuel economy and even more efficient combustion. This is also why these systems have air mass sensors, the amount of air is an important thing to measure in order to determine the right amount of fuel. Essentially fuel injection systems they have all of the complexity of a servo system, and the number of failure points compared to a direct linkage is huge, especially when you have a block that is split into two cylinder banks, V or Boxer.
- KennyBlanken 5y agoDrive by wire throttles have nothing to do "ensuring the right amount of fuel/air would be passed into the engine."
- theluketaylor 5y agoJason Cammisa did a great video explaining how modern accelerator pedals work and why: https://youtu.be/gKsCHx5NOMM https://youtu.be/gKsCHx5NOMM