[Csantucci]

disc, thank you.

[Coolhand101]

Hi

I'm trying to gear correctly a 4-speed manual gearbox DMU.

However the gear speeds are greatly surpassed from the "GearBoxMaxSpeedForGears", ie 1st gear is set for 15 mph but continues until 22.5mph. This also applies to the other speeds for gearbox max speed.

Also, im trying to simulate the idle force to be applied, when 1st gear is selected from neutral. Is this simulated in OR ?

One more thing, what is suppose to happen if the manual gear is changed, with power still applied ?

Thanks

[Csantucci]

I have also noticed that, unlike MSTS, speed increases above GearBoxMaxSpeedForGears.
As far as I remember, if you change gear with throttle>0, nothing terrible happens (as in MSTS).
If you look at the Force HUD, you will notice that motive force is = 0 when you select 1st gear with throttle at 0. So, no idle force seems active.

[Coolhand101]

Csantucci, on 08 September 2015 - 07:58 AM, said:

I have also noticed that, unlike MSTS, speed increases above GearBoxMaxSpeedForGears.
As far as I remember, if you change gear with throttle>0, nothing terrible happens (as in MSTS).
If you look at the Force HUD, you will notice that motive force is = 0 when you select 1st gear with throttle at 0. So, no idle force seems active.

I'm not sure atm what happens in the real world if you try to change gear while in power. Unless the gears are locked when the throttle is open.

The tractive effort in gear does fall, for example, from 15 mph( according to the HUD force ) but its very gradual.

As im testing my DMUs, i can report back, the overspeed for 15 27 41 and 70 mph gearbox speeds on level track.

Thanks

[Coolhand101]

OR version X3243

Right, with a 54 ton geared DMU - using GearBoxMaxSpeedForGears ( 15 27 41 70 )


15 mph = 22.5 mph

27 mph = 38.0 mph

41 mph = 53.6 mph

70 mph = 75.0* mph

The balancing speed of 75 mph was only because of train weight and resistance. With just the power car of 32 tonnes, this was 85 mph. This should not happen with geared DMUs as the weight should only affect acceleration and not top speed.

Just for reference, the UK Class 101 DMU 2-car can only balance on the level at 65.5 mph, even though its geared for 70 mph because of the one power car( not enough oomph ). A 3-car Class 101 DMU with 2 power cars(power twin) can get to 70mph on the level.

One more thing. I don't think OR can use this cab control while MSTS can:-

Information: Skipped unknown ControlType GEARS_DISPLAY in D:\PROGRAM FILES\MICROSOFT GAMES\TRAIN SIMULATOR\trains\trainset\MEP-Cravens105\CABVIEW\Class105CabView_OR.cvf:line 242

Thanks

[Csantucci]

I don't know about GEARS_DISPLAY, which in fact isn't present in OR, not even as token. Could you attach the .cvf block for this and the related .ace file, so that I can try it on a geared DMU?

[disc]

Coolhand101, on 08 September 2015 - 05:36 AM, said:

Hi

I'm trying to gear correctly a 4-speed manual gearbox DMU.

However the gear speeds are greatly surpassed from the "GearBoxMaxSpeedForGears", ie 1st gear is set for 15 mph but continues until 22.5mph. This also applies to the other speeds for gearbox max speed.

Also, im trying to simulate the idle force to be applied, when 1st gear is selected from neutral. Is this simulated in OR ?

One more thing, what is suppose to happen if the manual gear is changed, with power still applied ?

Thanks

Of course it goes over the max speed. That max speed is only to compute gear ratios. The gearbox never limits the max speed, what limits it is the engine max rpm, which rises to very high above the gear's max speed.
But in OR there is not RPM limiter (which is in all modern engines), nor engine failure or overheating due to high rpm (older engines). Same happens in a car.

Also there is no engine stalling simulated on low rpm.

[Csantucci]

There is a sound problem in OR in this behavior. In geared engines Variable2 is proportional to engines RPM, and reaches the maximum value of 1.0 when the maxspeed at the various gears as defined in the .eng file is reached. So if the engine may run at higher speeds than .eng maxspeed, from the .eng maxspeed to the effective maxspeed Variable2 stays at 1 and so the frequency of the motor sound (using a frequency curve) remains constant, which is completely unprototypical.

[Mike B]

disc, on 08 September 2015 - 12:16 PM, said:

Of course it goes over the max speed. That max speed is only to compute gear ratios. The gearbox never limits the max speed, what limits it is the engine max rpm, which rises to very high above the gear's max speed.
But in OR there is not RPM limiter (which is in all modern engines), nor engine failure or overheating due to high rpm (older engines). Same happens in a car.

Also there is no engine stalling simulated on low rpm.

For diesels at least, there has been a maximum speed for years. Even old mechanical-pump engines have a governor. The only way to overspeed those engines is to go downhill too fast for the gear you're in, or to try for compression braking using too low a gear (old diesels didn't have much of that absent a "jake brake" modification). My 1981 Rabbit Diesel was spec'd to deliver max power at the governed max of 4800 rpm (1.6l 4-cycle diesel, non-turbo) and could not be driven past that under power. So the max speed in a gear for a diesel-mechanical unit should be at the maximum engine speed (except possibly for high gear, where it might be at a lower engine speed due to aero limiting). If it's not, there may be an error in the .eng file or in ORTS. IIRC, MSTS worked correctly for things like the Kiha diesel car.

[disc]

Mike B, on 08 September 2015 - 01:34 PM, said:

For diesels at least, there has been a maximum speed for years. Even old mechanical-pump engines have a governor. The only way to overspeed those engines is to go downhill too fast for the gear you're in, or to try for compression braking using too low a gear (old diesels didn't have much of that absent a "jake brake" modification). My 1981 Rabbit Diesel was spec'd to deliver max power at the governed max of 4800 rpm (1.6l 4-cycle diesel, non-turbo) and could not be driven past that under power. So the max speed in a gear for a diesel-mechanical unit should be at the maximum engine speed (except possibly for high gear, where it might be at a lower engine speed due to aero limiting). If it's not, there may be an error in the .eng file or in ORTS. IIRC, MSTS worked correctly for things like the Kiha diesel car.

Maybe there are engines with RPM limiting, but i'm sure that there engines without limiting. GearBoxMaxSpeedForGears should only control the gear ratio. Maybe another parameter, for example RPMLimiter ( 0/1) should be implemented, then it could be set to match the real life behavior of the engine.

BTW: I've implemented the engine stalling here is the patch:  DieselEngine.cs.zip (1.24K)
Number of downloads: 240 is that ok? It's also the first try to make optional parameters for advanced diesel simulation.

It can be set like this:

ORTSDieselEngines ( 1
		Diesel (
			...
			StallingRPM ( 130 )
                        ...

If the RPM drops below the number, the engine stalls (stops). It's working also if this parameter is not given, or if the advanced diesel simulation is not used(so works with MSTS locomotives), then the stall RPM defaults to IdleRPM-1.