RPM Error at certain speed [1704]

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Baja_002
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RPM Error at certain speed [1704]

#1 Post by Baja_002 » 02 Oct 2014 20:20

So I've placed this in a bugs section since I really think it is a bug. Perhaps I'm wrong? If that's the case the "green meanies" should place this topic elsewhere.

Anyway, here is the problem (and I'll do my best to explain it).

When you set CC to, for example, at 60 km/h, it's all fine with the RPM gauge. However after the truck manages to achieve that speed something like 300 RPMs are lost; it's like the clutch slipped or something. As soon as you press the throttle the RPM goes (without pulling) up to the cca 1400 RPMs and then starts pulling effectively. Basically, there is an empty space between pulling range and cruise speed.

I do think it's a bug because when you reach 60 km/h at 1.300 RPMs, the truck should remain in that range unless there are some changes in the terrain that would affect the speed. Also it should raise as the truck accelerates or drop down as the truck decelerates (unless it's using full power)

Here are the two photos; in the first photo the truck has reached the desired speed (60 km/h) and I'm not using throttle at all. In the second photo I'm using throttle 100%. The problem is, what happens in between? It's cruising at around 1.200 and after I "floor it" nothing happens untill 1.500 PM.

Perhaps I'm not familiar with this or that's completely normal with certain gearboxes or whatever; but it's still a bug in my head until someone manages to explain it to me :lol:

Image

Image

And the overlapping of the two, to show you what I mean. Marked in PINK color
Image

*Any additional info is more than welcome*

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Cadde
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Re: RPM Error at certain speed

#2 Post by Cadde » 02 Oct 2014 20:50

This is by design, albeit not good design. (IMHO)
I can only imagine the reasoning for this but it may just be down to the fact that the average player isn't that good at driving so this is a smoothing factor to their erratic throttle (esp keyboard) input.

You can alter the clutch viscosity factor in physics.sii. Previously you had a direct clutch viscosity value, but now it's a factor. A multiplier.
Increasing the value makes your clutch grip better. I would look at doubling it (2.0) and adjusting from there to your liking.

Since my opinion on what constitutes a bug sometimes differ from that of the developers and other strongly opinionated people, i will not move it until it has been given some grace time.

EDIT: On a closely related side note, automatic transmissions (featuring torque converters) have this exact function... On take off.
Once they are up to speed and in a certain gear the TC is locked in sync with the input/output shafts. (Through gearing ofc)
On extended hiatus.

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Baja_002
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Re: RPM Error at certain speed

#3 Post by Baja_002 » 02 Oct 2014 21:02

Even though I'm not a professional and I do in fact use keyboard, this doesn't make any sense to me. Even if the RPMs are dropping it should be a much slower process than an instant drop to a certain number. Unless it uses an F1 configuration (and engine) with a almost instant RPM drop due to some heavy modifications for special purposes.

Nevertheless, it may sound completly irrelevant to most of the people but that's been bugging me for a while.

I'm interested, what does Max say about this, since he is the leading expert when it comes to explaining core game functions and options?

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Cadde
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Re: RPM Error at certain speed

#4 Post by Cadde » 02 Oct 2014 21:21

It drops because the synced speed is at the lower RPM, not the higher (engine providing torque) one. Or rather, if you had a set of pedals. The point where no torque at all is applied in either direction on the clutch/TC is the synced RPM.
Just try the setting i suggested and you will see that there's nothing (major) wrong with the game engine. It's just been set to a low viscosity value for "reasons".
I am sure Max will explain if he sees the thread.
On extended hiatus.

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Baja_002
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Re: RPM Error at certain speed

#5 Post by Baja_002 » 03 Oct 2014 20:19

Hmm yes, but if this was made to smooth out the bad driving (instant throttle for example via keyboard), wouldn't it be better to deliver the power across the wide range of RPMs but at more steady increase?

Right now, as it seems, it goes 1-0-1 meaning; 1 is active cruise control using power, 0 is for when you try to accelerate (area of the useless (?) power or no power at all) and then there is the area when you finally get to the power and start accelerating.

I hope you can understand my poor explanations :lol:


This is how it looks now (I know I'm awful at drawing these)
Image

And I think it should be like this
Image

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Cadde
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Re: RPM Error at certain speed

#6 Post by Cadde » 03 Oct 2014 23:16

I would fire up my Telemetry app and show you. But i am going to bed.

viewtopic.php?f=41&t=48931

EDIT: Though i haven't implemented logging of the throttle position in that plugin. :?
On extended hiatus.

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Baja_002
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Re: RPM Error at certain speed

#7 Post by Baja_002 » 03 Oct 2014 23:32

Not a problem, I'll have to take a look at that app tomorrow. I'm really interested in this "problem" now

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Max
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Re: RPM Error at certain speed

#8 Post by Max » 06 Oct 2014 13:06

this is long time known issue in our powertrain model.
very difficult to find and fix without breaking anything.
Nobody can tell you anything about it. Those who know about it aren't allowed to talk. And those who talk know nothing.

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Baja_002
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Re: RPM Error at certain speed [1704]

#9 Post by Baja_002 » 06 Oct 2014 13:55

I'm glad you are aware of this and that's not only my mind playing with me. :D

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Fender
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RPM tollerance in cruise

#10 Post by Fender » 15 Oct 2014 17:49

Hello everybody,

I see into ETS2 there is a strange tollerance when you drive with manual gear like if you use automatic gear...
I explain:
if you drive at 90km/h and press down gas pedal, your engine rpm, going up by 200-250 rpm and if you release gas pedal, rpm goes down 200-250 rpm...
This is normal if you drive with an automatic gear, but if you drive with a manual gear, rpm are not tollerance even velocity increase or decrease.
There is a way to have a direct reaction of rpm when we use a manual gear?
I tried to look into physic.sii, but noting... also transmission and engine...

I hope this is clear... my english is terrible :(
Last edited by Cadde on 16 Oct 2014 06:10, edited 1 time in total.
Reason: Merged similar topics

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