||This page describes some of the findings with Ian's Motion
software and the DIY Motion Platform III
One has to realize that there are
huge compromises in trying to mimic the forces during flight with a 3DoF
platform. For example, simulating fore-aft or sideways sustained forces can
only be achieved by tilting the platform to let gravity act on the occupant.
However the tilting action to achieve the desired angle can be unwanted in
itself, thus generating false force cues. To minimize the false cue, the
tilting action has to be slowed down, but this then results in time delays
of the desired force cue. Thus a compromise must be made between delays and
false force cues. It is also important to realize that the occupant position
with respect to the platform rotation point will affect the magnitude
in which the false force cues are felt. Generally, the closer the pilot's CG
is to the platform rotation point, the better.
For small GA airplanes: Small-GA.bff
For bigger commercial A/C: Boeing737.bff
During the extensive testing phase, I have come to realize that the best way to achieve the correct motion cues is by checking them out separately. To simplify things, I have almost always used the Cessna 172 in light turbulence weather conditions, doing traffic patterns, and a Boeing 737 for testing the bigger commercial aircraft.
Slow heave motion is not easily
felt. The heave motions need to be fast. (<0.5sec or so) therefore
heave range need to be a much as possible, to avoid maxing out. The
sensitivity of Ian's software needs to be tweaked a lot, and will vary for
Examining heave flight data also shows that FS2004 has some limitations
with respect to vertical accelerations on ground. Touch-down heave does not
seem to produce realistic results; It is far too much. We believe that FS
treats the whole airplane as a solid structure, without any gear suspension.
This would explain the steep high peaks during touch-down and riding over
grass land. This can be compensated by editing the .BFF file settings:
~to be continued~