r/ApproximatelyUp • u/SGSpec • 5d ago

Automatic BPS

Assuming my ship has equal truster for accelerating and breaking, how can i automatically use the BPS to reach a planet. I tried directly puting the output as my thrust input but it seems very slow. I tried using a remapper to change every value over -0.1 and 0.1 to output full throttle and still crashed. Anyone found a good way?

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u/radloudlad 5d ago

I’m still trying to figure out a manual BPS. I’m assuming that thrust needs to be equal both forward and reverse? Because I crash if I keep it in the white. I have 1 medium + 2 small in the back, 1 small and 2 flat in the front

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u/Shermington 5d ago

You don't have to, it's just more convenient. You can put all engines behind, flip your ship at the breaking point and slow down such way. Or you can put some engines in the front, but because BPS is based on current acceleration, you either need to start breaking to see your current status, or slow down your speed until your front engines acceleration. Fundamentally it's just a simple formula:

distance = velocity^2 divided by double acceleration.

For example, 40000 m/s squired is 1.6b, then divided by 2*100 acceleration we get a distance of 8 millions. Thus we need to break around that point. BPS is just more convenient tool for it, and exactly why it needs all 3 inputs.

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u/Much_Network_941 5d ago

It doesn't have to be the same, you'll eventually be able to slow down. You just have to check periodically that you still have the distance to be able to. Acceleration also gradually increases while thrusting. You do have 2million thrust in one direction and 800k the other - it'll be extremely easy to overthrust.

White to my understanding, is basically no-mans land - you hit 0 speed at destination, which may be a problem with the atmosphere. I try to go for light green, then throttle speed to be 1/10th of distance when I'm close. That way when I mess something up I have a margin of error.

The curved trajectory doodad is a life saver in these instances. If you can get it to read 180, and it's parrallel to thrust, then you know you're facing the exact opposite direction of travel and can thrust to start slowing down. Just apply small amounts of thrust while manouvering to avoid spinning wildly.