• bstix@feddit.dk
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    1 year ago

    Everything digital in a car is often handled by the “entertainment” system. Like a glorified radio. Manufacturers like to keep that as separate system from the car, so it’s replaceable and upgradable and fail safe from the actual operation of the car.

    Also, many car designs (of the cars on the road today) are 20 years old, when digital screens in cars had yet to prove reliability. Nobody wanted to risk having to replace screens just to show the speed. Some brands have had digital speedometers for ten years or so.

    Anyway, digital speedometers also calculate the speed by magnets, so the GPS and speedometer might still show different speeds depending on the size of wheels just as badly as an analogue one. Again, it has to, because the operation of a car should not be dependent on a satellite system, f.i. in tunnels.

    So in short: Digital speedometers are not more accurate and they’re introducing points of potential failure.

    • Thorry84@feddit.nl
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      1 year ago

      I’m sorry but this is just wrong. Cars are very much digital for years now. Everything is connected together using CAN bus and handled by a computer. This computer is completely seperate from the entertainment system, which often isn’t even connected to the CAN bus.

      My car is 10 years old, not expensive and almost everything is digital on it. For example the gas pedal is simply a pedal connected to a sensor and a motor. The motor allows for force feedback and automatic actuation, whilst the sensor let’s the computer know what I intend to do. Depending on what mode the car is in and what it sensors are saying, it’ll interpret the signal differently.

      All of the parts of the car communicate digitally and without this the car wouldn’t be able to run. This has been the case for decades now. If you have a fuel injected car, it needs a computer to run at all, it needs things like a lambda sensor to run properly. Things like ABS and collision detection is handled through a computer, etc.

      The speed as displayed on the analog speedometer is almost certainly read by a digital sensor and communicated through the bus as a digital signal. The computer then puts that signal into the actuator to move the needle. It’s not like a belt and pulley system connected to the dash. Other systems in the car need to know the speed as well, for example the variable power steering needs to know if you are parking, driving through town or on the highway. This is all done digitally.

      • eneka@lemmy.world
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        1 year ago

        Yup, my old 1999 BMW had analog gauges and a lcd screen for other information like the Odometer, temp, maintenance information, etc. but you were able to enter a “secret” menu where it displayed the actual speed, there was also information like fuel tank levels and battery voltage as well!

    • TristanFi@lemmy.world
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      1 year ago

      This is partly true, but regulations do allow for a computer screen digital version of the basic safety display, as long as it can be demonstrated to be reliable and work without other systems like the infotainment system, and many manufacturers have implemented this.

      IMO I think the answer to the OP is “it was a stylistic choice”

      • bstix@feddit.dk
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        1 year ago

        Yes definitely, the choice of a mechanical arrow or digital display is optional and stylistic. I’m just explaining why the digital speedometers aren’t better currently.

        Like you say, the problem is that the reading of speed has to be done without secondary systems. The digital display does seem more precise because it shows an exact digit, but it’s not really. It just shows a digit instead of a mechanical arrow, which is still electronic btw.

        In order to make it more precise we’d need secondary systems to calculate the speed. It doesn’t have to be GPS, it could be done by other sensory inputs. Modern cars have cameras and it wouldn’t be difficult to make a proper calculation using those or something else.

        I also wish I had a precise fuel gauge, but what’s the point really. It’s not possible to calculate a range anyway, because it depends on the future driving.

        It’s a “need to have” versus “nice to have”. People who need to have a precise speed probably have secondary systems for that specifically.