154 lines
3.2 KiB
Plaintext
154 lines
3.2 KiB
Plaintext
run "library/lib_math".
|
|
|
|
declare function WaitForEngineStart{
|
|
wait until AnyEngineActive().
|
|
}
|
|
|
|
declare function GetDrag{
|
|
parameter localGravity.
|
|
return ship:sensors:acc:mag + localGravity.
|
|
}
|
|
|
|
declare function GetDragDir{
|
|
parameter localGravity.
|
|
parameter dir.
|
|
return vDot(ship:sensors:acc, dir) + localGravity.
|
|
}
|
|
|
|
declare function AnyEngineActive{
|
|
list engines in allEngines.
|
|
for eng in allEngines{
|
|
if eng:ignition {
|
|
return true.
|
|
}
|
|
}
|
|
return false.
|
|
}
|
|
|
|
declare function GetIsp{
|
|
LIST ENGINES IN allEngines.
|
|
declare local totalThrust is ship:maxThrust.
|
|
local sum is 0.
|
|
local weights is 0.
|
|
for eng in allEngines{
|
|
if eng:IGNITION and not eng:flameout{
|
|
local w is eng:AVAILABLETHRUST / totalThrust.
|
|
local ispW is eng:isp * w.
|
|
set sum to sum + ispW.
|
|
set weights to weights + w.
|
|
}
|
|
}
|
|
return sum / weights.
|
|
}
|
|
|
|
declare function GetMaxMassFlow{
|
|
LIST ENGINES IN allEngines.
|
|
local sum is 0.
|
|
for eng in allEngines{
|
|
if eng:IGNITION and not eng:flameout{
|
|
set sum to sum + eng:maxmassflow.
|
|
}
|
|
}
|
|
return sum.
|
|
}
|
|
|
|
|
|
|
|
|
|
declare function CalculateSuicideBurnDuration
|
|
{
|
|
parameter isp.
|
|
return CalculateBurnDuration(verticalSpeed, isp, ship:mass, GetMaxMassFlow() * 1000).
|
|
}
|
|
|
|
declare function CalculateBurnDuration
|
|
{
|
|
parameter dv.
|
|
parameter burnIsp.
|
|
parameter initialMass.
|
|
parameter massFlow.
|
|
|
|
set dv to abs(dv).
|
|
local exp is -dv / (burnIsp * constant:g0).
|
|
local massRatio is ApproximateExp(-exp).
|
|
local finalMass is initialMass / massRatio.
|
|
local fuelUsed is initialMass - finalMass.
|
|
|
|
if massFlow <= 0{
|
|
return 0.
|
|
}
|
|
|
|
return fuelUsed / massFlow.
|
|
}
|
|
|
|
|
|
declare function CalculateSuicideBurnAltitude
|
|
{
|
|
parameter vertSpeed.
|
|
parameter localGravity.
|
|
parameter tgtAltitude is 0.0.
|
|
parameter drag is 0.0.
|
|
|
|
local vertAcc is CalculateAverageDecceleration(localGravity).
|
|
local burnAltitude is ((vertSpeed^2) / (2 * (vertAcc))).
|
|
return burnAltitude + tgtAltitude.
|
|
}
|
|
|
|
declare function CalculateSuicideBurnAltitudeV2
|
|
{
|
|
|
|
parameter vertSpeed.
|
|
parameter localGravity.
|
|
parameter tgtAltitude is 0.0.
|
|
|
|
|
|
local vs is vertSpeed * -1.
|
|
local a is CalculateAverageDecceleration(localGravity).
|
|
local dt is 0.05.
|
|
local result is 0.0.
|
|
local h is alt:radar.
|
|
|
|
until vs <= 0 {
|
|
set vs to vs + a * dt.
|
|
set result to result + vs * dt.
|
|
|
|
if result > h { return result. }
|
|
}
|
|
|
|
return result.
|
|
}
|
|
|
|
|
|
declare function CalculateAverageDecceleration{
|
|
parameter localGravity.
|
|
local maxVertAcc is (ship:availablethrust / ship:mass) - localGravity.
|
|
|
|
return maxVertAcc + localGravity.
|
|
}
|
|
|
|
declare function GetLocalGravity{
|
|
parameter curAltitude is -1.
|
|
|
|
if curAltitude = -1 {
|
|
set curAltitude to altitude.
|
|
}
|
|
return body:mu / (curAltitude + body:radius)^2.
|
|
}
|
|
|
|
declare function CalculateTimeToImpact{
|
|
parameter vertSpeed.
|
|
parameter curAltitude.
|
|
parameter gravity.
|
|
parameter tgtAltitude is 0.0.
|
|
|
|
if gravity <= 0 or curAltitude <= 0{
|
|
print "[warn]: invalid altitude or gravity.".
|
|
return 0.0.
|
|
}
|
|
|
|
local vs is abs(vertSpeed).
|
|
local g is gravity.
|
|
local hRel is curAltitude - tgtAltitude.
|
|
local disc is ((vs^2) + (2 * g * hRel)).
|
|
return (vs + sqrt(disc)) / g.
|
|
} |