Touch-down bump and Engine start/stop shudder generation
V2.80 of the FS9/X version of the
BFF 3 DOF motion driver adds a feature for generating touchdown
bumps and engine start/stop shudders.
The features are enabled using
manual settings in the .bff configuration file.
NOTE some experimentation with the
settings will likely be required to obtain the best results for
individual platform drives. The default settings described below are
for guidance only.
Touch down can often be felt in
the motion cue when it causes a big enough spike in the vertical
acceleration of the aircraft. If you make good landings however the
acceleration spike might be small and no bump will make through into
the cue naturally.
In V2.80 of the driver artificial
TD bumps can be produced using the following settings in the .bff
;Touchdown bump effects
;Touchdown bump sine wave frequency (Hz)
;Touchdown bump amplitude (as a proportion of VaMAX above - ie as a
proportion of the max heave cue range). Set = 0 to disable effect.
;Touchdown bump time to decay to zero - in seconds
;Heave acceleration inhibit during touchdown bump, =1 to inhibit
normal heave accel on TD, =0 to allow as normal ?
;Duration in seconds for which the on-ground indicator is held at 0
(in-air) when aircraft first lifts-off. To prevent TD bump if OG
indicator toggles on lift off
The bump effect is a decaying sine wave
initiated by the TD event in the flight sim which is added to the
heave cue output. The frequency, amplitude and duration of the wave
can be set using the above parameters to allow tuning of the effect
to suit your platform drive.
Parameter TD_Acc_Disable adds the option to block the
"real" heave acceleration input to the motion cue whilst the
generated wave is active. This can produce unrealistically uniform
TD bumps however which are independent of the quality of the actual
Parameter TD_HIA_Duration provides an option to hold
the FSX TD indicator in the "in-air" position on lift off. This is
to prevent false TD bumps from being generated if the lift off isn't
clean and the indicator "toggles" momentarily before the aircraft
fully leaves the ground.
Engine Start/Stop Shudders:
The start/stop shudders are generated by a decaying
sine wave added to the Roll axis of the motion cue which is
initiated by start/stop of engine No. 1
The amplitude, frequency and duration of the decaying
sine wave can be adjusted to suit using the parameters described
;Shudder sine wave frequency (Hz)
;Shudder amplitude (as a proportion of LaMAX above - ie as a
proportion of the max roll cue range). Set = 0 to disable effect.
;Shudder time to decay to zero - in seconds
Some experimentation will be
needed to obtain the best results for your platform.