fivekm

//Approaching from 5km beneath station
clearscreen.
set pi to 3.1415926535897932384626433832795028841971693993751058209749445923.
set mu to 3.986*(10^14).
ag1 off.
set target to "LIESS".
set lateraloffset   to 0.
set verticaloffset to -5000.
rcs on.
sas off.
gear off.
lock steering to prograde + r(0,0,180).

set maneuverSpeed to 1.

//functions
function verticaldist {
  set vdist to target:altitude-ship:altitude.
	return vdist.
}.
function verticalinputFunction {
	if abs(verticalDistance2+extraH) > 10 {
		set vver to (verticalDistance2-verticalDistance1)/(dt).
		if verticaldistance2+extraH > 0 {
			set ms to -maneuverSpeed.
		}. else {
			set ms to  maneuverSpeed.
		}
		set vverError to ms-vver.
		set vertinput  to kpv*vverError.
    ///////////////////////////////////////////
	}. else {
		set sverError to (verticaldistance2+extraH).
		set vver to (verticalDistance2-verticalDistance1)/(dt).
		set vertinput to -((kps*sverError)+(kds*vver)).
	}.
	return vertinput.
}.

////////////////////////////////////////////////////////////////////////////////
//defining values and gains
set kpv to 1.
set kps to .1.
set kds to 2.

set latinput to 0.
set verticalinput to 0.
set extraH to verticaloffset.
set vver to 0.

set desireSMA to target:orbit:semimajoraxis-5000.
set desiredT to 2*pi*sqrt((desireSMA^3)/mu).

//Sub 5 KM station keeping
until ag1 {
	if 2 > 1 {
		set verticalDistance1 to verticaldist().
		set t1                to time:seconds.
		print "Vertical Difference "+round(verticalDistance1)+" m".
		print " ".
		print "Vertical Input "+round(100*verticalinput).
		wait 0.2.
		clearscreen.
		set verticalDistance2 to verticaldist().
		set t2                to time:seconds.
		set dt                to t2-t1.
	}. //this is just so i can hide it easily
	////////////////////////////////////////////
	set verticalinput to verticalinputfunction().
	///////////////////////////////////////////
	set ship:control:top       to verticalinput.
	set foreinput to 0.1*(desiredT-ship:orbit:period).
	set ship:control:fore to foreinput.
	print "Foreward Input "+(100*round(foreinput)).
}.
ag1 off.

unlock steering.
sas on.
set ang to 2. //between ship and target positions
set theta to 1.
until   ang < theta {
	set targpos to target:position+ship:body:position.
	set ang to vang(ship:body:position,targpos).
	set dist to 1000*13.8.//m. value obtained from space mech notes
	set theta to (180/pi)*(dist/ship:body:position:mag).
	print "Awaiting Burn".
	print "Loop ends at zero: "+round(1000*(ang-theta)).
	wait 0.1.
	clearscreen.
}
set warp to 0.
sas off.
lock steering to prograde + r(0,0,180).

//this is about 1.4 m/s dv prograde
//foreward acceleration averages .4 m/s2
set v0 to ship:velocity:orbit:mag.
set ship:control:fore to 1.
wait until ship:velocity:orbit:mag>(v0+3.4).
set ship:control:neutralize to true.
unlock steering.
sas on.
until ag1 {
	print "Altitude Difference: "+round(target:altitude-ship:altitude)+" meters".
	wait 0.1.
	clearscreen.
}
ag1 off.
run twokmclosing.