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AI Systems: Difference between revisions

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AI Systems (view source)

Revision as of 05:46, 27 June 2006

33 bytes added ,  27 June 2006
→‎Using Interpolation Tables: add degree symbol
(→‎Using Interpolation Tables: add degree symbol)
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| 90 KIAS
| 90 KIAS
|-
|-
| 10* flaps
| 10° flaps
| 90 KIAS
| 90 KIAS
|-
|-
| 20* flaps
| 20° flaps
| 70 KIAS
| 70 KIAS
|-
|-
| 30* flaps
| 30° flaps
| 60 KIAS
| 60 KIAS
|-
|-
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When the pilot extends the flaps "one notch" they will extend to "10*" etc. In the property tree, these 4 steps will typically be normalised to 0.00, 0.33, 0.66, 1.00.  This will differ from aircraft to aircraft. If the aircraft does not have equal extensions for each "notch" of flaps, the values observed may be; 0.00, 0.10, 0.30, 0.66, 1.00. Modeling this non-linear extension using "factor, offset, min/max" would be extremely difficult if not impossible. Modeling it using interpolation tables is very easy, as you shall see.
When the pilot extends the flaps "one notch" they will extend to "10°" etc. In the property tree, these 4 steps will typically be normalised to 0.00, 0.33, 0.66, 1.00.  This will differ from aircraft to aircraft. If the aircraft does not have equal extensions for each "notch" of flaps, the values observed may be; 0.00, 0.10, 0.30, 0.66, 1.00. Modeling this non-linear extension using "factor, offset, min/max" would be extremely difficult if not impossible. Modeling it using interpolation tables is very easy, as you shall see.


For sim animations, the actual physical rotation of the control surface in the real world needs to be researched; this may reveal a linear or non-linear relationship between "nominal flap extension indicator" and physical rotation of the surface. That is, "10 degrees of flap" might only involve rotating the flap surface 5 degrees around its axis in the wing structure. In our 0,10,20,30 scenarios, assuming a linear relationship, 30 degrees of flap would result in the flap being rotated 15 degrees around its wing axis. Therefore the normalised /surface-positions/flap-pos-norm property would have a factor of 15 applied to the rotate animation
For sim animations, the actual physical rotation of the control surface in the real world needs to be researched; this may reveal a linear or non-linear relationship between "nominal flap extension indicator" and physical rotation of the surface. That is, "10 degrees of flap" might only involve rotating the flap surface 5 degrees around its axis in the wing structure. In our 0,10,20,30 scenarios, assuming a linear relationship, 30 degrees of flap would result in the flap being rotated 15 degrees around its wing axis. Therefore the normalised /surface-positions/flap-pos-norm property would have a factor of 15 applied to the rotate animation
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these figures are nonsense but are used to illustrate a point:
these figures are nonsense but are used to illustrate a point:


  flaps retracted(0*) = 0 x 60 = 0, (offset=-30) = -30, (min= -10) = -10
  flaps retracted(0°) = 0 x 60 = 0, (offset=-30) = -30, (min= -10) = -10
  flaps extended(10*) = 0.33 x 60 = 20, (offset=-30) = -10, (min= -10) = -10
  flaps extended(10°) = 0.33 x 60 = 20, (offset=-30) = -10, (min= -10) = -10
  flaps extended(20*) = 0.66 x 60 = 40, (offset=-30) = 10, (min= -10/max=10) = 10
  flaps extended(20°) = 0.66 x 60 = 40, (offset=-30) = 10, (min= -10/max=10) = 10
  flaps extended(30*) = 1.00 x 60 = 60, (offset=-30) = 30, (max=10) = 10
  flaps extended(30°) = 1.00 x 60 = 60, (offset=-30) = 30, (max=10) = 10


more realistically, offset and min max are not used for flaps, only a factor.
more realistically, offset and min max are not used for flaps, only a factor.


say 27*, this represents the maximum rotation of the 3-D component in the model around its defined axis.
say 27°, this represents the maximum rotation of the 3-D component in the model around its defined axis.


  flaps retracted(0*) = 0 x 27 = 0
  flaps retracted(0°) = 0 x 27 = 0
  flaps extended(10*) = 0.33 x 27 = 9
  flaps extended(10°) = 0.33 x 27 = 9
  flaps extended(20*) = 0.66 x 27 = 18
  flaps extended(20°) = 0.66 x 27 = 18
  flaps extended(30*) = 1.00 x 27 = 27
  flaps extended(30°) = 1.00 x 27 = 27


from this it can be seen that the 3-D object will be rotated 0, 9, 18 & 27* to represent the 0, 10, 20 & 30* deployment of the flaps.
from this it can be seen that the 3-D object will be rotated 0°, 9°, 18° & 27° to represent the 0°, 10°, 20° & 30° deployment of the flaps.


Relating this back to the speeds above:
Relating this back to the speeds above:
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this gives a stepped effect, where the movement is limited to 1knt of airspeed. That is the 3-D object will linearly move from 9* to 18* while the aircraft looses speed from 70knts to 69knts. This behaviour will make the need for an upper and lower limit of a stepped value obvious.
this gives a stepped effect, where the movement is limited to 1knt of airspeed. That is the 3-D object will linearly move from 9° to 18° while the aircraft looses speed from 70 knots to 69 knots. This behaviour will make the need for an upper and lower limit of a stepped value obvious.


a simplified table of:
a simplified table of:
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