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If my steering wheel isn't connected to my front wheels mechanically, that's asking for a lot of trust. Previously a severe mechanical issue would be the only

If my steering wheel isn't connected to my front wheels mechanically, that's asking for a lot of trust. Previously a severe mechanical issue would be the only thing to worry about. Maybe on an EV with always connected and charged batteries it would be better, but on ICE I can imagine a number of ways the electrical system suddenly fails and now the wheel does nothing, even if just for a short lag. At least on brake by wire ICE systems I could let engine braking slow me if the brake system fails somehow (even if I have to blow the engine to save my life, worth the trade).

amluto 3y ago
Having previously driven a car with a mildly unreliable power steering system, it’s an extremely good thing that the power steering was backed up with a mechanical linkage (that worked very well — it was surprisingly subtle when the power steering crapped out at 30mph). A drive-by-wire system had better be a lot more reliable and also notice impending failures.
- dkjaudyeqooe 3y ago
  > it was surprisingly subtle when the power steering crapped out at 30mph It's not a problem at those speeds, having it crap out when turning slowly and sharply around fast traffic is much more likely to be deadly.
  - dotancohen 3y ago
    The opposite is true. Those old AMCs without power steering were just as easy to steer on the highway as any other car (once you managed to get up to speed) but the parking lot was a chore and parallel parking was neigh impossible.
    - bombcar 3y ago
      Fancier power steering systems basically fully disengage at speed because you don’t need them; they’re for moving the wheels when you’re stopped or nearly so.
    - dkjaudyeqooe 3y ago
      I guess I got the wording wrong because that's exactly what I meant.
      - amluto 3y ago
        The most dangerous situation I encountered was turning left across traffic from a stop.
        dkjaudyeqooe 3y ago
        Yeah that's exactly what I was thinking about (and thought I wrote, but the downvotes say otherwise). If your steering assist conks out just as you're trying to turn at slow speed you could end up heading into oncoming traffic, at an angle at least. It's actually pretty dangerous, good thing you don't drive it any more.
        amluto 3y ago
        A combination of whatever fiddling the mechanic did and making sure the fluid was topped off seemed to solve the issue. Also, it was a good, if somewhat old, car, and the mechanical steering was quite good. I was able to steer it without much difficulty at pretty much any speed even in no-power-steering mode. But yes, I agree, unpredictable steering response is dangerous.
- devmor 3y ago
  I personally cannot stand power steering systems. There’s always a dead zone and the feedback is delayed, in some vehicles more noticeably than in others, but it’s always there. I feel like I have had several close calls that would have been accidents for sure had I been driving with power steering.
  - lathiat 3y ago
    What car do you have without power steering? Or, are you referring to electric as opposed to hydraulic power steering? I haven't seen a car without power steering since the early 00s (which was a 90s car). The steering deadzone is not purely a function of power steering. Some of it is design or could be attributed to that, but a bunch of it also comes from slop in the physical connections in the steering column, as well as the suspension bushings, your tyre profile, etc.
    - amluto 3y ago
      I once drove an early car with an electric steering assist system. (It was either a renta or a test drive, I think it was an American car, and I don’t remember what brand or model.). It was terrible. There was essentially no feedback from the road to the wheel. These systems have improved.
    - devmor 3y ago
      It turns out I was mistaken! I haven’t done enough research to determine the actual cause of the effect I have noticed. It might be hydraulic vs electric but I don’t want to make that assumption and be wrong again - I’m going to have to research the steering in other cars I’ve noticed that issue in.
      - lathiat 3y ago
        There’s definitely a different feel to the electric motor driven assist. Though there are just many different implementations probably the specific one you had was particularly quirky. Relatedly I had a Hyundai i30 for a while which has a well known fault where the plastic gear connection (called a Spyder Bush) from the electric motor to the steering column would break. Resulting in slop and a clunk. Not hard to imagine similar failures or bad design.
otherme123 3y ago
Mechanic connections can, and do, fail. Ask Ayrton Senna. AFAIK, steer by wire are already doing full redundancy, like it was a plane. There has been a number of plane accidents related to physical connection between the yoke and the actuators (cables loosing tension under high temperatures, or cut/trapped on a deck failure). Electric cables does not suffer that, and they are easily doubled. SbW makers are already making software that does constant surveilance of the system, something that traditional systems has never done. The number of dead people caused by the steering column going straight through their chest in a collision is huge. That shouldn't happen with SbW. I hate the trend towards car controls in a screen, but Drive by Wire sounds like a real advance towards better cars to me. DbW without redundancies and continuous tracking could be a safety issue, but with them I don't think it's an issue. Fly by Wire has a good safety record.
- pompino 3y ago
  >Fly by Wire has a good safety record. Because there are dozens of people helping keep each plane safe.

amluto 3y ago

Having previously driven a car with a mildly unreliable power steering system, it’s an extremely good thing that the power steering was backed up with a mechanical linkage (that worked very well — it was surprisingly subtle when the power steering crapped out at 30mph). A drive-by-wire system had better be a lot more reliable and also notice impending failures.

dkjaudyeqooe 3y ago
> it was surprisingly subtle when the power steering crapped out at 30mph It's not a problem at those speeds, having it crap out when turning slowly and sharply around fast traffic is much more likely to be deadly.
- dotancohen 3y ago
  The opposite is true. Those old AMCs without power steering were just as easy to steer on the highway as any other car (once you managed to get up to speed) but the parking lot was a chore and parallel parking was neigh impossible.
  - bombcar 3y ago
    Fancier power steering systems basically fully disengage at speed because you don’t need them; they’re for moving the wheels when you’re stopped or nearly so.
  - dkjaudyeqooe 3y ago
    I guess I got the wording wrong because that's exactly what I meant.
    - amluto 3y ago
      The most dangerous situation I encountered was turning left across traffic from a stop.
      - dkjaudyeqooe 3y ago
        Yeah that's exactly what I was thinking about (and thought I wrote, but the downvotes say otherwise). If your steering assist conks out just as you're trying to turn at slow speed you could end up heading into oncoming traffic, at an angle at least. It's actually pretty dangerous, good thing you don't drive it any more.
        amluto 3y ago
        A combination of whatever fiddling the mechanic did and making sure the fluid was topped off seemed to solve the issue. Also, it was a good, if somewhat old, car, and the mechanical steering was quite good. I was able to steer it without much difficulty at pretty much any speed even in no-power-steering mode. But yes, I agree, unpredictable steering response is dangerous.
devmor 3y ago
I personally cannot stand power steering systems. There’s always a dead zone and the feedback is delayed, in some vehicles more noticeably than in others, but it’s always there. I feel like I have had several close calls that would have been accidents for sure had I been driving with power steering.
- lathiat 3y ago
  What car do you have without power steering? Or, are you referring to electric as opposed to hydraulic power steering? I haven't seen a car without power steering since the early 00s (which was a 90s car). The steering deadzone is not purely a function of power steering. Some of it is design or could be attributed to that, but a bunch of it also comes from slop in the physical connections in the steering column, as well as the suspension bushings, your tyre profile, etc.
  - amluto 3y ago
    I once drove an early car with an electric steering assist system. (It was either a renta or a test drive, I think it was an American car, and I don’t remember what brand or model.). It was terrible. There was essentially no feedback from the road to the wheel. These systems have improved.
  - devmor 3y ago
    It turns out I was mistaken! I haven’t done enough research to determine the actual cause of the effect I have noticed. It might be hydraulic vs electric but I don’t want to make that assumption and be wrong again - I’m going to have to research the steering in other cars I’ve noticed that issue in.
    - lathiat 3y ago
      There’s definitely a different feel to the electric motor driven assist. Though there are just many different implementations probably the specific one you had was particularly quirky. Relatedly I had a Hyundai i30 for a while which has a well known fault where the plastic gear connection (called a Spyder Bush) from the electric motor to the steering column would break. Resulting in slop and a clunk. Not hard to imagine similar failures or bad design.

otherme123 3y ago

Mechanic connections can, and do, fail. Ask Ayrton Senna. AFAIK, steer by wire are already doing full redundancy, like it was a plane. There has been a number of plane accidents related to physical connection between the yoke and the actuators (cables loosing tension under high temperatures, or cut/trapped on a deck failure). Electric cables does not suffer that, and they are easily doubled. SbW makers are already making software that does constant surveilance of the system, something that traditional systems has never done. The number of dead people caused by the steering column going straight through their chest in a collision is huge. That shouldn't happen with SbW. I hate the trend towards car controls in a screen, but Drive by Wire sounds like a real advance towards better cars to me. DbW without redundancies and continuous tracking could be a safety issue, but with them I don't think it's an issue. Fly by Wire has a good safety record.

pompino 3y ago
>Fly by Wire has a good safety record. Because there are dozens of people helping keep each plane safe.