How to adjust helicopter parameters, helicopter model version 1
0 General information
Please read this file for a
description of helicopter parameters.
1 Suggested steps
It is assumed that values for mass and inertia already are correct.
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Copy and modify the values of an existing model.
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Set all of the following values to zero:
aero.yaw.dist, aero.pitch.dist,
aero.roll.dist,
aero.yaw.moment_mul, aero.yaw.off,
aero.yaw.cp_to_yaw,
aero.roll.ForwardToRoll,
aero.yaw.vane, aero.pitch.vane
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Start CRRCSim, set wind speed and thermals to zero. Load the model
you want to adjust. Save settings. Easiest way to try settings is
to just quit CRRCSim (hit 'q'), edit and save parameter file, start
CRRCSim again.
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If power.fixed_pitch is set, adjust aero.pitch.off
and power.automagic.F to set maximum climb rate and climb
rate at neutral stick.
For a collective pitch heli, adjust aero.pitch.off,
aero.pitch.ctrl
and power.automagic.F.
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Adjust aero.yaw.ctrl, aero.pitch.ctrl, and
aero.roll.ctrl for full stick rotation rates in rad/second.
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Does the heli rotate around the correct point? Adjust its center of
gravity.
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Adjust lift in ground effect with GroundEffect.climb.mul and
GroundEffect.climb.exp.
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Fly around and adjust aero.yaw.vane,
aero.pitch.vane, and aero.speed.damp.
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Remove aero.pitch.damp and aero.pitch.dist. They
are taken from aero.roll.damp and aero.roll.dist
if they don't exist.
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Adjust aero.roll.damp and aero.roll.dist.
You may want to tweak Disturbance.tau_filter and
Disturbance.time, too.
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Do you think aero.pitch.damp and aero.pitch.dist
should differ from
aero.roll.damp and aero.roll.dist? If this is the case:
define them.
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Adjust aero.yaw.damp, aero.yaw.damp_min_rel, and aero.yaw.dist.
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If the model has a heading lock gyro, set
aero.yaw.HeadingHold to something greater than zero and
aero.yaw.moment_mul to one.
Otherwise, you should ideally increase aero.yaw.moment_mul
to one and adjust aero.yaw.off and
aero.yaw.cp_to_yaw. Setting aero.yaw.moment_mul to
something smaller than one makes this easier -- but maybe less
realistic.
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Adjust increase of disturbances in ground effect:
GroundEffect.dist.mul and
GroundEffect.dist.exp.
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Finally, you may want to tweak aero.roll.ForwardToRoll.