Mirror from SNAPKITTYWEST: src/sim/guidance.ts

src/sim/guidance.ts

@@ -0,0 +1,22 @@
+import {clamp,RAD} from './math';
+import {navigation} from './navigation';
+import type {FlightState} from './state';
+export function guide(s:FlightState){
+ if(!s.guidance||!s.systems.navigation||!s.systems.computers||s.phase==='ABORT')return;
+ const n=navigation(s);
+ if(s.phase==='PRELAUNCH'||s.phase==='COUNTDOWN')return;
+ // Target a 220 km apogee; radial velocity closes as apogee approaches.
+ const targetApo=220000;
+ let targetVertical=n.altitude<1500?150:Math.sqrt(Math.max(0,2*n.gravity*(targetApo-n.altitude)))*0.55;
+ targetVertical=clamp(targetVertical,0,1050);
+ if(n.apoapsis>targetApo)targetVertical=Math.min(targetVertical,Math.max(-50,(targetApo-n.altitude)/200));
+ const thrustAccel=(s.stage===0?7600000:1300000)/s.mass;
+ const radial=clamp((targetVertical-n.vertical)/35+n.gravity-n.horizontal*n.horizontal/(n.altitude+6371000),-thrustAccel,thrustAccel);
+ const targetPitch=n.altitude<700?0:Math.acos(clamp(radial/thrustAccel,-1,1))/RAD;
+ s.pitch+=clamp(targetPitch-s.pitch,-0.65,0.65);
+ s.yaw=90;s.roll*=0.99;
+ s.throttle=clamp(3.5*9.80665/thrustAccel,0.2,1);
+ if(s.q>34000)s.throttle=Math.min(s.throttle,0.55);
+ if(n.periapsis>180000&&n.apoapsis<400000)s.throttle=0;
+ if(s.orbitAchieved)s.throttle=0;
+}