From 15f1f1ed549c0e33d76f05b0bfca73afe002179c Mon Sep 17 00:00:00 2001
From: Valentin Verdier <valentin@aztrom.fr>
Date: Thu, 30 Dec 2021 14:08:06 +0100
Subject: [PATCH] add circularization maneuver

---
 boot/automate_01.ks |  3 ++-
 libmaneuver.ks      | 61 ++++++++++++++++++++++++++++++---------------
 2 files changed, 43 insertions(+), 21 deletions(-)

diff --git a/boot/automate_01.ks b/boot/automate_01.ks
index 0b6dffa..394a051 100644
--- a/boot/automate_01.ks
+++ b/boot/automate_01.ks
@@ -12,11 +12,12 @@ global g_direction is 90.
 global g_throttle is 1.
 global g_apoapsis is 80000.
 global g_gt_angle is 10.
-global g_gt_velocity is 60.
+global g_gt_velocity is 53.
 
 man_launch(g_direction, g_throttle).
 man_gravity_turn(g_direction, g_gt_angle, g_gt_velocity, g_apoapsis).
 release().
+wait until ship:altitude > 70000.
 man_node_circularize("apo").
 man_node_exec().
 release().
diff --git a/libmaneuver.ks b/libmaneuver.ks
index e5cc5fb..c02f209 100644
--- a/libmaneuver.ks
+++ b/libmaneuver.ks
@@ -21,6 +21,30 @@ global function man_get_dv_hohmann {
 	return vf - vi.
 }
 
+global function man_get_duration {
+	parameter p_dv, p_throttle.
+	local total_thrust is 0.
+	local total_isp is 0.
+	local engs_count is 0.
+	list engines in engs.
+
+	for eng in engs {
+		if eng:ignition = true and eng:flameout = false {
+			set total_thrust to total_thrust + eng:availablethrust * p_throttle.
+			set total_isp to total_isp + eng:isp.
+			set engs_count to engs_count + 1.
+		}
+	}
+
+	local f is total_thrust * 1000.
+	local m is ship:mass * 1000.
+	local e is constant():e.
+	local p is total_isp / engs_count.
+	local g is 9.80665.
+
+	return g * m * p * (1 - e ^ (-p_dv / (g * p))) / f.
+}
+
 global function man_node_circularize {
 	parameter p_pos.
 	local dv is 0.
@@ -33,38 +57,40 @@ global function man_node_circularize {
 		set tn to time:seconds + ship:orbit:eta:periapsis.
 	}
 
+	print "=> Planning circularization maneuver : " + round(dv, 1) + " m/s".
 	add node(tn, 0, 0, dv).
 }
 
 global function man_node_exec {
 	local nd is nextNode.
+
+	print "=> Preparing maneuver".
+	
+	local dur is man_get_duration(nd:deltav:mag, 1).
+
+	wait until nd:eta <= (dur / 2) + 60.
 	lock steering to nd:burnvector.
 
-	lock accel to ship:maxthrust / ship:mass.
-	lock dur to nd:deltav:mag / accel.
-
 	wait until nd:eta <= (dur / 2).
-
+	print "=> Executing maneuver".
+	local ti is time:seconds.
+	local tf is ti + dur.
 	lock throttle to 1.
-	wait until dur < 0.5.
+	wait until tf - time:seconds < 0.25.
 	lock steering to ship:facing.
 	lock throttle to 0.25.
-	local dv is nd:deltav:mag.
-	until nd:deltav:mag > dv {
-		set dv to nd:deltav:mag.
-	}
+	set dur to man_get_duration(nd:deltav:mag, 0.25).
+	set ti to time:seconds.
+	set tf to ti + dur.
+	wait until tf - time:seconds <= 0.
 	lock throttle to 0.
 
-	unlock dur.
-	unlock accel.
-
 	remove nd.
 }
 
 global function man_launch {	
 	parameter p_direction, p_throttle.
-	print "=> man_launch".
-	
+	print "=> Launch".
 	lock throttle to p_throttle.
 	lock steering to ship:facing.
 
@@ -73,29 +99,24 @@ global function man_launch {
 	stage.
 
 	wait until ship:altitude >= 150.
-	print "    - Alignment...".
 	lock steering to heading(p_direction, 90).
 }
 
 global function man_gravity_turn {	
 	parameter p_direction, p_angle, p_velocity, p_apoapsis.
-	print "=> man_gravity_turn".
-
+	print "=> Gravity Turn".
 	wait until ship:velocity:surface:mag >= p_velocity.
-	print "    - Rotation...".
 	local gt_start is heading(p_direction, 90 - p_angle).
 	lock steering to gt_start.
 
 	wait until vang(ship:facing:vector, gt_start:vector) < 1.
 	wait until vang(ship:srfprograde:vector, ship:facing:vector) < 1.
 
-	print "    - Follow prograde...".
 	lock steering to heading(p_direction, 90 - vang(ship:up:vector, ship:srfprograde:vector)).
 
 	wait until ship:orbit:apoapsis >= 0.95 * p_apoapsis.
 	lock throttle to 0.3.
 	wait until ship:orbit:apoapsis >= p_apoapsis.	
-	print "    - Apoapsis OK".
 	lock throttle to 0.
 	wait 1.
 	stage.