58 lines
1.6 KiB
Plaintext
58 lines
1.6 KiB
Plaintext
// Functions for calculating thrust values.
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@lazyglobal off.
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// Returns the throttle value you should use to achieve the
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// target TWR. If TWR can't be achieved, returns 1.0. (full throttle)
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function ThrottleToTWR {
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parameter targetTWR is 1.5.
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local m is SHIP:MASS.
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local g is 9.81.
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if HAS_GRAV_SENSOR = true {
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set g to SHIP:SENSORS:GRAV:MAG.
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}
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return min((targetTWR*m*g)/SHIP:AVAILABLETHRUST, 1.0).
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}
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// Calculates the ship's current TWR.
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function TWR {
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local m is ship:mass.
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local g is 9.81. // fallback to this approximation that doesn't deal with
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// altitude change.
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if HAS_GRAV_SENSOR = true {
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set g to SHIP:SENSORS:GRAV:MAG.
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}
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local t is THROTTLE * SHIP:AVAILABLETHRUST.
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return t/(m*g).
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}
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// Check for various sensors and set appropriate global constants.
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// Currently only checks for grav sensor, as that's the only one used by this library.
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global HAS_GRAV_SENSOR is false.
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function SensorCheck {
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local SensorList is 0.
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list SENSORS in SensorList.
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for s in SensorList {
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if s:type = "grav" {
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print "Gravometric sensor detected".
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set HAS_GRAV_SENSOR to true.
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return.
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}
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}
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set HAS_GRAV_SENSOR to false.
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}
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function BurnTime {
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parameter dV.
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list ENGINES in en.
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local f is en[0]:MAXTHRUST * 1000. // Engine Thrust (kg * m/s²)
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local m is SHIP:MASS * 1000. // Starting mass (kg)
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local e is CONSTANT():E. // Base of natural log
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local p is en[0]:ISP. // Engine ISP (s)
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local g is 9.80665. // Gravitational acceleration constant (m/s²)
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return g * m * p * (1 - e^(-dV/(g*p))) / f.
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}
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