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[egoexpress]

So far I am actually not sure in which forum section this topic will fit.

I have revived my SCN5 seat-mover recently, after a pc performance upgrade (quadcore, hd6950, etc...), and I encountered the same principal problem with the SCN5 actuators, like the last time I have been tweaking arround with game profiles, SCN5 speed and accelleration settings.
Although setting the Profiler break, switching time, receive time and switching timeout all to 1ms improved motion quality alot, there is a problem for which I am not able to find a workarround.

I am able to get longitudinal g-forces played back almost perfect.
As well I am able to get the lateral and vertical g-forces to play back almost perfectly.

But what I am not able, is to get them played back with reasonable quality all together.

Here is the reason why:
For vertical and lateral g-forces I get best results with settings arround accell~600...800, and speed~10000

BUT, for longitudinal g-forces, I get best results with settings arround accell~150...200, and speed~5000 (accell setings above 200 feels like neck-braking while gear-shifiting in a F1)

Problem: I am just able to choose accell and speed globally for everything.

So either I set accell/speed low, to get a good accelleration feeling, but almost no track surface feedback, or I set accell/speed high, which causes my neck almost to brake while gear shifting, and which causes the jittering in effect 27. (long-g-forces) to almost superpose all other effects, so that everything is shaking that much, that you cant tell anymore what exactly is causing which particular actuator movement. It just shakes the hell out of me.

Using smothness for 27 (long.) improves the throttle motion quality alot. At least since I set the outputs to 1ms. But with SCN5 accell settings above 200, the jittering gets noticable again.

From my point of view, the accell and speed values need to be adjustable for every math table effect, and not just global.
Global accell/speed settings are a really bad horse-trade.

What do you guys think? Do I miss something?

Regards

[ledfoot]

I also agree with you ego. I prefer a higher acceleration setting on my sim but I have a lot of dampening which makes a big difference. I would like to see adjustable speed and acceleration settings per math effect as well if it were possible.

[bvillersjr]

The smoothing value in the G-Force plugin can help to solve some of the problem, but cannot solve it completely. That said, proper utilization of this will make a nice improvement.

I recently switched to a new profile approach that it a bit better suited to the consecutive mathiline execution of X-Sim. In a perfect world, we wouldn't be limited in this manner but that is an completely different topic and probably a pointless one anyway so I'll spare you the theory.

[Nima]

hi,
in this profil viewtopic.php?f=100&t=3063&p=31138&hilit=#31138 between number 1 and 10 is a new createt 27 effect were you want.you only must tweak the values 27 for your car and play.what do you play?

[egoexpress]

After I did the simple slider HW they can decide by themself and it works for all.

Although your tip with external speed/accelll setting per pot does not relate to the problem, it is a very usefull feature anyway, which I will definately implement as well.

But it does not concern the issue, that motion quality would improve a lot, if SCN5 speed and accelleration could be set for each and every math effect independantly, and not just per user and globally for every effect in the math table.

Really high speed and reaction time is neccessary to simulate road surface, BUT it is preferrable to have rather slow movements when accellerating. I like to feel the accelleration movement with a duration of round about 1-2 seconds (depending F1 or sportscar), with rather soft shifting effect. But this is impossible when accell setting is above 300, as the smoothness effect gets replaced by jittering (because the actuators accellerate too fast).

Btw, how many outputs per second do you guys have ~ in the SCN5 plugin window? I have ~120outs/second.

Regards

[Nima]

hi,
i have 220 outs/second

[bleco]

I personally use the joystick plugin of the profiler and combine it with the acceleration and speed output of both scn5 with a new axis math line. Then I have a hardware slider pot of a joystick on the right side of my sim to increase and decrease the needed value

Interresting ... sticky tuturial post ? looks very easy when reading it but how do we do this ??

motion quality would improve a lot, if SCN5 speed and accelleration could be set for each and every math effect independantly, and not just per user and globally for every effect in the math table.

I agree ... It's hard to create a very well balance profile when having 1 general actuators speed/accel setting ...

Btw, how many outputs per second do you guys have ~ in the SCN5 plugin window? I have ~120outs/second.

I am getting constant 200 outputs/sec with the cheapest serial adapters

in this profil viewtopic.php?f=100&t=3063&p=31138&hilit=#31138 between number 1 and 10 is a new createt 27 effect were you want.you only must tweak the values 27 for your car and play.what do you play?

Don't want to get off topic but is there any topic in this forum that explains how to create a profil like this? ... with copy and combine ... Can someone (mission for Papifix ;-) ) explain the logic behind this profile in a separated topic ?




Bleco

[Frakk]

The ramping curve (acceleration, speed, deceleration) is the very last link in the chain just like adjusting PID gains, it is a setting of the hardware that is meant to be set up once, when the actuators are started. At this point in data, all of the effects are mixed together and practically impossible to apply different acceleration values for different effects.

In a perfect world, the ramping curve should be set to the fastest response, where the actuator doesn't miss steps, -20% safety margin. We want the fastest response for the most surface detail.

The only proper way is to filter the unwanted fast movements on the specific effects (27), before they are mixed into the bunch, otherwise everything else will suffer. A more sophisticated low pass filter algorithm could improve it significantly.

Mechanical dampening is a workaround, but it still doesn't fix the issue and wastes energy in the rubber.

[bleco]

The only proper way is to filter the unwanted fast movements on the specific effects (27), before they are mixed into the bunch...

Which specific filter ?




Bleco

[Frakk]

At this time the only effect specific filter is the "smoothness" slider in 1:1 G-Force.

Further more there are 3 filter plugins: Mean value filter, Smoothness filter, and Spike Filter. Using these filters the order of the math line has to be specific: Effects to be filtered -> Filters -> Unfiltered Effects added, because we only want to filter specific effects.

The mean value filter will slow down the rate of change (acceleration), that's what I would try first.