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fgdata/Aircraft/Generic/soaring-instrumentation-sdk.nas
Colin Geniet 59b9aeb271 Glider vario: Add nasal controller for sound pitch
Adds a sound frequency controller to glider-instrumentation-sdk.nas,
used for the ilec-sc7. This allows:
- Simpler <sound>.xml files to integrate the glider variometer.
- More accurate frequency scaling (frequency scales exponentially with
vertical speed, so that perceived changes in pitch are linear with
vertical speed).
- Fixes that the variometer sound would not drop at negative vertical
speeds.
2020-02-27 20:05:40 +01:00

442 lines
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# Glider Instrumentation Toolkit
#
# Copyright (C) 2013-2014 Anton Gomez Alvedro
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# Features:
# + Total energy compensated variometer
# + Netto variometer
# + Relative (Super Netto) variometer
# + Configurable dampener for simulating needle response time
# + Configurable averager
# + Speed to fly computer
#
# TODO:
# - add wind correction to speed-to-fly
# - final glide computer
io.include("updateloop.nas");
var MPS2KPH = 3.6;
var sqr = func(x) {x * x}
var InstrumentComponent = {
parents: [Updatable],
output: 0,
reset: func { me.output = 0 },
};
# This alias is for keeping backwards compatibility.
# TODO: Refactor aircrafts that use it and remove this.
var Instrument = UpdateLoop;
##
# Helper generator for updating a property on every element update
#
# Example:
#
# var needle = Dampener.new(
# input: probe,
# dampening: 2.8,
# on_update: update_prop("/instrumentation/variometer/te-reading-mps"));
#
# See Aircraft/Instruments-3d/glider/vario/ilec-sc7.nas and
# Aircraft/Generic/soaring-instrumentation-sdk.nas for usage examples.
# You can also refer to the soaring sdk wiki page.
var update_prop = func(property) {
func(value) { setprop(property, value) }
};
# InputSwitcher
# Selects output from one of multiple components given as inputs
#
# var lcd_controller = InputSwitcher.new(
# inputs: Vector of objects connected to the input
# active_input: (optional) Input number that is active at start
# on_update: (optional) function to call whenever a new output is available
var InputSwitcher = {
parents: [InstrumentComponent],
new: func(inputs, active_input = 0, on_update = nil) {
return {
parents: [me],
inputs: inputs,
active_input: active_input,
on_update: on_update
};
},
select_input: func(input_number) {
me.active_input = input_number;
me.update();
},
update: func {
me.output = me.inputs[me.active_input].output;
if (me.on_update != nil) me.on_update(me.output);
}
};
# PropertyReader
# Makes a property available at its output. Its purpose is to adapt properties
# to the component model used by the library.
#
# var temperature = PropertyReader.new(
# property: Property to read from
# scale: Scale factor applied to the property value (output = scale * prop)
var PropertyReader = {
parents: [InstrumentComponent],
new: func(property, scale = 1) {
return {
parents: [me],
property: property,
scale: scale
};
},
update: func {
me.output = me.scale * getprop(me.property);
}
};
# YawString
# The most important instrument in a glider. Simple, cheap and effective!
#
# var string = YawString.new(
# on_update: update_prop("/instrumentation/yaw-string/deflection-deg");
var YawString = {
parents: [InstrumentComponent],
new: func (on_update = nil) {
return {
parents: [me],
on_update: on_update
};
},
update: func {
var airspeed = getprop("velocities/airspeed-kt");
var noise = (airspeed < 54) ?
math.sin(math.pi * airspeed / 54) * rand() : 0;
me.output = noise + getprop("orientation/side-slip-deg");
if (me.on_update != nil) me.on_update(me.output);
}
};
# TotalEnergyProbe
# Computes total energy variation by reading current airspeed and altitude
#
# var probe = TotalEnergyProbe.new(
# on_update: (optional) function to call whenever a new output is available
var TotalEnergyProbe = {
parents: [InstrumentComponent],
altitude: 0, # meters
airspeed: 0, # m/s
new: func(on_update = nil) {
return {
parents: [me],
on_update: on_update
};
},
reset: func {
me.airspeed = getprop("/velocities/airspeed-kt") * KT2MPS;
me.altitude = getprop("/position/altitude-ft") * FT2M;
me.output = 0;
},
update: func(dt) {
var altitude_now = getprop("/position/altitude-ft") * FT2M;
var airspeed_now = getprop("/velocities/airspeed-kt") * KT2MPS;
me.output = (altitude_now - me.altitude) / dt;
me.output += (sqr(airspeed_now) - sqr(me.airspeed)) / (19.62 * dt);
me.altitude = altitude_now;
me.airspeed = airspeed_now;
if (me.on_update != nil) me.on_update(me.output);
}
};
# Dampener
# Simple IIR exponential filter. Appropriate and efficient for simulating
# mechanical needle dampening.
#
# var needle = Dampener.new(
# input: Object connected to the dampeners input.
# dampening: (optional) Time constant for the filter in seconds
# scale: (optional) Scale factor applied to the input signal before filtering
# on_update: (optional) function to call whenever a new output is available
var Dampener = {
parents: [InstrumentComponent],
dampening: 0, # time constant of the exponential filter (sec)
scale: 1,
new: func(input, dampening = 3, scale = 1, on_update = nil) {
return {
parents: [me],
input: input,
dampening: dampening,
scale: scale,
on_update: on_update,
};
},
update: func(dt) {
var alfa = math.exp(-dt / me.dampening);
me.output = me.output * alfa + me.input.output * me.scale * (1 - alfa);
if (me.on_update != nil) me.on_update(me.output);
}
};
# Averager
# Provides a windowed moving average of its input signal. Window size is
# set on construction, and is given in samples (i.e. not seconds).
#
# var averager = Averager.new(
# input: Object connected to the averagers input.
# size: (optional) window size in samples
# on_update: (optional) function to call whenever a new output is available
var Averager = {
parents: [InstrumentComponent],
new: func(input, buffer_size = 25, on_update = nil) {
var m = { parents: [me] };
m.input = input;
m.on_update = on_update;
m.size = buffer_size;
m.sum = m.wp = 0;
m.buffer = setsize([], buffer_size);
m.reset();
return m;
},
reset: func {
me.sum = me.wp = me.output = 0;
forindex (var i; me.buffer)
me.buffer[i] = 0;
},
update: func {
var new_value = me.input.output;
me.sum = me.sum + new_value - me.buffer[me.wp];
me.output = me.sum / me.size;
me.buffer[me.wp] = new_value;
if ((me.wp += 1) == me.size)
me.wp = 0;
if (me.on_update != nil) me.on_update(me.output);
}
};
# PolarSolver
# Helper object required for advanced soaring instrumentation.
# Provides McCready speed-to-fly computations assuming a parabolic glider polar
# (this approximation is frequently used in real instruments as well).
#
# Polar coeficients provided on construction correspond to the equation:
# sink = coefs[0] * airspeed^2 + coefs[1] * airspeed + coefs[2]
#
# Note that sink is considered positive. Negative sink means.. lift!
#
# var solver = PolarSolver.new(
# polar_coefs: [0.000364277, -0.0479199, 2.31644]
# mass: Reference mass in Kg used while obtaining the polar above
var PolarSolver = {
min_sink: 0, # minimum sink m/s, according to glider polar
new: func(polar_coefs, mass) {
var m = { parents: [me] };
m.reference_coefs = polar_coefs;
m.coefs = polar_coefs;
m.reference_mass = mass;
m.total_mass = mass;
m.min_sink = m.coefs[2] - (sqr(m.coefs[1]) / (4 * m.coefs[0]));
return m;
},
set_total_mass: func(mass) {
me.total_mass = mass;
var load_factor = math.sqrt(mass / me.reference_mass);
# Update active polar
me.coefs[0] = me.reference_coefs[0] / load_factor;
me.coefs[2] = me.reference_coefs[2] * load_factor;
me.min_sink = me.coefs[2] - (sqr(me.coefs[1]) / (4 * me.coefs[0]));
},
speed_to_fly: func(mc, airmass_sink) {
var speed = (mc + me.coefs[2] + airmass_sink) / me.coefs[0];
return (speed > 0) ? math.sqrt(speed) : 0;
},
ld: func(airspeed) {
return aispeed / me.sink(airspeed);
},
sink: func(airspeed) {
return me.coefs[0] * sqr(airspeed)
+ me.coefs[1] * airspeed + me.coefs[2];
}
};
# NettoVario
# The Netto variometer substract glider's sink rate for current airpseed from a
# total energy reading. The resulting value is airmass' lift/sink in m/s.
#
# var netto = NettoVario.new(
# te_probe: Object providing a total energy reading
# polar_solver: Object providing a McCready implementation
# on_update: (optional) function to call whenever a new output is available
var NettoVario = {
parents: [InstrumentComponent],
new: func(te_probe, polar_solver, on_update=nil) {
return {
parents: [me],
probe: te_probe,
polar: polar_solver,
on_update: on_update
};
},
update: func {
me.output = probe.output
+ me.polar.sink(probe.airspeed);
if (me.on_update != nil) me.on_update(me.output);
}
};
# RelativeVario
# The Relative (aka Super Netto) variometer tell you what climb rate would you
# get if you slowed down to optimal thermaling speed.
#
# var snetto = RelativeVario.new(
# te_probe: Object providing a total energy reading
# polar_solver: Object providing a McCready implementation
# on_update: (optional) function to call whenever a new output is available
var RelativeVario = {
new: func(te_probe, polar_solver, on_update=nil) {
return {
parents: [me, NettoVario.new(te_probe, polar_solver, on_update)]
};
},
update: func {
me.output = probe.output
+ me.polar.sink(probe.airspeed)
- me.polar.min_sink;
if (me.on_update != nil) me.on_update(me.output);
}
};
# SpeedCmdVario
# The speed command variometer tells you how fast or slow your airspeed is with
# respect to the optimal speed-to-fly (computed according to McCready theory).
#
# var speedcmd = SpeedCmdVario.new(
# te_probe: Object providing a total energy reading
# polar_solver: Object providing a McCready implementation
# netto: (optional) Object providing a Netto reading
# on_update: (optional) function to call whenever a new output is available
var SpeedCmdVario = {
parents: [InstrumentComponent],
mc: 0, # mccready setting
new: func(te_probe, polar_solver, netto = nil, on_update = nil) {
return {
parents: [me],
polar: polar_solver,
probe: te_probe,
netto: netto or NettoVario.new(te_probe, polar_solver),
update_netto: (netto == nil),
on_update: on_update
};
},
update: func {
if (me.update_netto) me.netto.update();
var target_speed = me.polar.speed_to_fly(me.mc, -me.netto.output);
me.output = me.probe.airspeed * MPS2KPH - target_speed;
if (me.on_update != nil) me.on_update(me.output);
}
};
# Vario sound pitch controller
# Computes the frequency factor for a variometer sound.
#
# var vario_sound = SoundPitchController.new(
# input: Object connected to the pitch controller input, e.g. a variometer reading.
# max_pitch: (optional) Maximum sound frequency factor, the output will be
# in the range [1/max_pitch, max_pitch], default 2.
# max_input: Value of input for which max_pitch is reached.
# on_update: (optional) function to call whenever a new output is available
var SoundPitchController = {
parents: [InstrumentComponent],
new: func(input, max_input, max_pitch = 2, on_update = nil) {
return {
parents: [me],
input: input,
max_pitch: max_pitch,
max_input: max_input,
on_update: on_update,
};
},
update: func {
var input = math.clamp(me.input.output, -me.max_input, me.max_input);
me.output = math.pow(me.max_pitch, input / me.max_input);
if (me.on_update != nil) me.on_update(me.output);
},
};