View Single Post
  #5  
Old November 7th 13, 09:57 PM posted to rec.autos.simulators
Mario Petrinovic
external usenet poster
 
Posts: 253
Default Axis sensitivity (FFB)

Tony R:
Mario Petrinovic:
> Tony R:
> Mario Petrinovic:
>> No, sensitivity should be 100%.

>
> Mario, 50% is fully linear, 0% and 100% are the extreme curves allowing
> more or less sensitivity within the initial movement of the controller.
> This is normally for using joysticks with a small amount of travel.
>
> Fully linear is normally used with wheels especially those with 900
> degrees of rotation.
> --------------------------------------------------------------------------------
>
> Thanks for the info, Tony.
> Well, I really don't know where you have that info from.
> As far as I know, sensitivity is sensitivity.
> You, yourself is actually mentioning linearity and unlinearity in
> your answer. Look at what you wrote, "50% is fully linear,...".
> So, if you are talking about linearity, wouldn't this slider be
> called "linearity", or something. We have slider in iRacing for adjusting
> brake linearity, which behaves similarly to what you are describing.
> Now, I had thorough testing of this, and it really behaves like it
> is a sensitivity slider. Even more, the kind of car control that I
> experienced with this slider being at 100% reminds me on what I saw fast
> drivers are doing. So, this would tell me that they also are having this
> slider at 100%.
> Actually, my testing showed me that it is senseless to have this
> slider at any other position than 100%, because if FFB is less than 100%
> sensitive, than this unsensitivity introduces its own slack into FFB,
> which messes up FFB.


It isn't FFB sensitivity but axis sensitivity. You are right it is just
the same as adding a brake curve in iRacing only for the steering axis.
Anything other then 50 is applying a curve - be that more sensitive with
the initial movement and tailing off (highly sensitive) or less
sensitive with initial movement and increasing with range (low).

It does seem a bit counter intuitive as you might expect 100 to be fully
linear.

Nothing really wrong with setting it high - you get fast steering with
relatively little movement. You could probably achieve that with a lower
steering ratio (faster rack) or through short calibrating what is 90
degrees in the iRacing calibration.

In most race driving conditions you aren't winding enough lock on to
feel the non linearity although some people notice (and hate) it.

You probably wouldn't want that high sensitivity around centre in a
stock car though
--------------------------------------------------------------------------------

Ok.
Now, you've mentioned, with setting this high, you get fast steering
with relatively little movement.
The problem is, FFB has its time component. It doesn't tolerate
latency. For FFB to work properly, time component must be correct.
Now, through my testing it is obvious that FFB works correctly ONLY
at sensitivity = 100%. I tried 25 different positions (amongst those were
95,96,97,98,99,100), and didn't test all those positions just causally, but
properly (yes, it takes a lot of time for this), and it is obvious that on
my system (and, believe me, I took extreme care that everything else that I
know affects FFB, is correct on my system) ONLY 100% works like it should. I
mean, this isn't like 99% is close, 98% is less close, 97% even less close,
it is like 0 to 99 don't work like they should (although, obviously, the
closer you get to 100%, the closer it is to being correct), and only 100%
really works.
Now, there could be two reasons for that.
1) The Immersion company used the shortest sensitivity while
developing FFB, because this gives the least latency
2) iRacing messed up something AGAIN.
I believe that it is the 1) this time, that is true.

Ads