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Comment by yrral | Hacker News Reader

Is this even an issue? Presumably without a steer by wire system a human would not be able to turn the wheel this fast. Also the delay looks longer than it actually is because of the slow-mo. Say this is playing at 25% speed and it is delayed by 1/2 a second, that means at regular speed the delay is only 125ms.

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125ms is pretty bad though. In an online game that'd be borderline unacceptable lag... no local system should be THAT slow?

Try it yourself here to see how bad that feels: https://www.skytopia.com/stuff/lag.html

That page also links to a great video on what it's like on a touchscreen: https://www.youtube.com/watch?v=vOvQCPLkPt4

1/8 of a second is terribly slow. Delays like that fuck up your perception/feedback loop. If you put on headphones, and listen to your own speech delayed by that amount of time, you can hardly speak (delayed auditory feedback). If you have to control a device that delays that much, you're prone to overreacting, and then entering a run-away correction cycle, which isn't nice in a heavy, fast moving machine.

Yeah, it's really not great. To be fair, though, in the dialup days, many of us learned to cope with that ping while still playing Quake 2 or whatever. You can adapt, it just takes a while, and you learn to lead your target. You can make similar adaptations to vehicle control (like playing a racing game on a really laggy old-school plasma TV), but it's not pleasant.

I really wouldn't want highway drivers in that monster truck to have any barriers to their reactions, especially with its nontraditional crumple zone :(

There are differences between Quake and driving. One would be respawning.

Lol yes, slightly different situations.

Power assist lets you turn a wheel with one finger at any ratio the manufacturer chooses... at most you'll get a lag in the assist but not in the mechanical movement (and I'd be amazed if that is perceptible with electric assist let alone hydraulic)

There isn't really any excuse for this.

It's hardly a performance car so perhaps it's not a big issue, but it really should not the there and should be fixed.

Because the steering ratio is variable, the movement shown in the video is about the equivalent of two full turns of a normal steering wheel. I tend to agree with the parent, it'd be hard for a human to equal this performance.

You know, I rewatched the video, and you convinced me.

There's not actually THAT much latency (delay between input and response). There IS some acceleration curve being applied (X degrees of input = X^Y degrees of steering, buffered over time), but that's totally different. It's probably safer this way vs suddenly jerking the actual wheels back and forth.

Steering backlash is always non-zero but for a new vehicle should be imperceptible. But that isn't a direct analogy for lag. With backlash, once you've taken it up it's gone. Any continued turn in the same direction translates to wheel movement without delay.

125ms is...horrendous. Electronic steering controls are part of my day job and usually you're going for about 5ms delay. If you're more than 10ms, it's a problem.

I agree with your observation, although it seems unpopular at the moment. It’s clear the video is slowed down and seeing how his hands respond at the end of his action, it looks like he’s throwing the wheel very quickly.

The tires start moving immediately, so it looks more like a limit in how quickly they change direction. It appears laggy because they don’t finish the movement when he does. They do respond right away when he shifts his arms a little in the middle of the video.

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