
Your Gas Gauge as User Experience - jeffclark
http://autos.aol.com/article/gas-gauge/?ncid=AOLCOMMautogenlfpge0006&a_dgi=aolshare_email
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CountHackulus
As far as user experience goes, having a non-linear gas gauge is, for me at
least, infuriating. My 94 Accord had a fairly linear gas gauge, I knew that
when I got to 1/4, there was roughly 1/4 tank of gas left. Now, in my new
Mazda 6, there's a definite non-linear effect, and have been surprised more
than once by how little distance I get out of that last "1/4 tank."

I find it somewhat dangerous to have a non-linear gas gauge, especially at the
bottom end if you're not used to it. Let's say I just drove 150km and used a
1/2 tank of gas, then I see a gas station and a sign that says that the next
gas station is in 100km. Given that I've got a 1/2 tank left, I should have
1/6 of a tank to spare when I get there right? Well, no, turns out that it's
cutting it really close. My gas light goes on when I'm about 10km away from
the gas station. Not a pleasant experience at all.

I'm seriously considering doing some math can hooking up some sort of
microcontroller to the gas gauge to undo the "calibration" done at the
factory. Really wish there was some kind of bolt-in mod for this.

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quanticle
What I do is to ignore the gas gauge completely. I keep track of the miles
driven. My driving is fairly consistent, and I know the rated capacity of my
fuel tank, so I can fairly easily determine when I should fill up based on how
many miles I have driven.

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carbocation
I like your style. However, this can be a problem when you're switching
between city and highway driving. My vehicle gets 1.5x the mileage (300 miles
vs 200) on a full tank when I drive on highways as opposed to in a city. So it
is helpful to have a sense of what the gas gauge is telling you.

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switch007
300 miles? The tank in my 1.6 VW Golf is 55 litres (12 imperial gallons) and I
get between 420 and 500 miles out of a full tank (I get around 37mpg combined
and 42mpg on highways). Do your cars generally use more fuel than European
cars? Do automatic cars really affect the gas usage /that/ much?

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carbocation
I drive a monstrosity.

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hinathan
This isn't rocket science. My Audi (and BMW before that) have nice clean
digital displays of predicted miles remaining based on driving history, tank
capacity, and measured fuel consumption. Turns out 'How far can I go?' is a
better metric than 'About how much of a tank is left?'.

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tofumatt
My 2010 MINI (BMW-made) has the same deal, and you could use the stats it
gives you (kilometres until empty, average kilometres/litre, and actual tank
size in litres) to calculate what's left in your tank, but why not just add it
to the displays that already exist?

I also notice European cars (Audi, BMW, MINI, Saab, even VW etc.) tend to be
more accurate and linear than American/Japanese vehicles. But that's just me.

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ratsbane
When I was a kid my family had a Mercedes diesel and my aunt had a Cadillac. I
remember noting that the Mercedes fuel gauge was labeled "Tank" and marked off
in a round arc with equal distances between each of the markings. The Cadillac
had a square gauge labeled "Fuel Data Centre" with a needle sweeping across
markings in a straight line. The Mercedes was much more practical.

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achompas
The pinnacle of gas gauge experience has to be the Toyota Prius. The article
was interesting, but I was a bit bummed to see no reference to my favorite
driving experience.

Here's an the Prius's in-dash energy monitor:
<http://www.youtube.com/watch?v=dqP_eS_f1qY>

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sp332
The Honda CR-Z has trees which lose their leaves if you drive inefficiently,
and you have to drive really carefully to get them to grow back.

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c2
The Honda CR-Z is a great car, it's too bad so much focus is paid to 0-60
times.

I think it's a really innovative blend of driver involvement, education about
efficient driving, and sporty driving dynamics. A really cool "hack" of a car.

~~~
sp332
Reminds me of the problems Transmeta had with their low-power processors. The
laptops made with them had like 8-hour battery life, but at that time,
everyone was looking at performance benchmarks and thought they were crap.
Intel bought them and later used a bunch of their tech in mobile processors. I
think people will eventually learn to appreciate good mileage, but the first 5
years or so will be pretty rough in the market.

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barrkel
On the other hand, the "full reserve" is handy when you need to return a
rental with a "full" tank of gas.

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hugh3
Or un-handy not, when it turns out that the last bastard to use the car left
it two gallons from full.

In a car rental context it's basically a transfer of wealth from the honest to
the dishonest.

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barrkel
It's less a case of dishonesty than it is that airports (the usual place for
car rentals) are a bit out of the way and often have uncompetitive fuel
prices.

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hugh3
Yeah, I'll generally fuel up a few miles from the airport, but not fifty miles
from the airport. As long as everyone has a similar idea of what's acceptable
it works out fine.

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harry
The gas gauge is just another 'idiot light' to me. It doesn't really tell me
anything reliable but it does spur further action. Similar to how a
maintenance required light lets me know I need to plug in the code reader and
check it out. When the gauge indicates low, I'll pay attention to how much
mileage I'm expecting and then time the next fill-up around that.

(Tracking mileage is done on my phone. Using the data stored there I can
accurately gauge how many miles I can get using the odometer. I've done this
for the entire life of my truck and I can peg a 3500 mile roadtrip's cost
within 5$)

That said - I feel that I would prefer an accurate reading on the tank status
through the gauge to be standard. I wouldn't feel so uncertain when driving
someone else car past the last gas station for 50m en route to Vegas.

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mootothemax
I came across an interesting illustration of some calibration taking place a
couple of years ago. To cut a long story shut, I lifted up the hood/bonnet and
was dismayed to see petrol spewing everywhere from a leak in one of the hoses
supplying the inlet manifold.

At this point I'd noticed that the petrol gauge was reading around an eight of
a tank left. I fitted a replacement hose, and the gauge shot up to over 1/2 a
tank! This happened about two years ago in a '92 BMW E36 325, and I can only
guess at what the ECU was interpreting from all of this...

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InclinedPlane
There are similar UX concerns for progress bars. Users will perceive an
operation as taking less time if the progress bar accelerates (i.e. the last
half takes less time than the first half) than if it decelerates, regardless
of actual time taken. This was an annoying problem with file copying in Vista
where the typical behavior was to progress along to close to 100% then hang
there for a while, which people hate experiencing.

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mikeknoop
This article is impeccable -- I have consciously observed every effect noted
in the article on my 97 Ford Explorer.

