5 ms·

https://www.reddit.com/r/spacex/comments/gigmfh/spacex_iss_docking_simulator/fqfzatb/ https://www.reddit.com/r/spacex/comments/gigmfh/spacex_iss_d... does it i

https://www.reddit.com/r/spacex/comments/gigmfh/spacex_iss_docking_simulator/fqfzatb/ https://www.reddit.com/r/spacex/comments/gigmfh/spacex_iss_d... does it in one line but it's kind of cheating.

Eduardo3rd 6y ago
browser console is a pretty under rated feature. I wish it was used more extensively to teach people how to code. so many cool little hacks you can do on public web pages that cement new concepts quickly.
yreg 6y ago
Anything is a oneliner when you erase all the `\n`s
- jylam 6y ago
  Python begs to differ
  - vulcan01 6y ago
    You can add semicolons at the end of python lines to replace \n's when calling from the command line. python3 -c "n=1;print(n)"
    - pferde 6y ago
      How does it deal with code blocks normally defined by indentation? (As an aside, indentation being part of syntax is the only thing keeping me disgusted with python - I like the language otherwise.)
      - uryga 6y ago
        it doesn't :) though it works fine if your terminal allows multiline input: python -c " for x in stuff: this(x) that(x) " at some point i even wrote a hacky little wrapper that let you use braces and replaced¹ them with spaces+newlines, something like this: pyc-wrap "for x in stuff { this(x); that(x); }" i can dig the code up if you need it :) ======== though after that i sort of went of the deep end adding perl-style "it" ($_) variables for loop variables: for stuff { this($); that($); (yes, closing braces at the end were optional...) and for the result of the previous line: 2; $+1; hex($); # roughly translates to: x = 2; x = x+1; x = hex(x); surprisingly pleasant to use for shell-like tasks actually! edit: almost forgot - if during execution you used a name `foo` not found in locals/globals, `foo` was treated as an external command, and resolved to something like lambda *args: os.system('foo', *args) so that you could (sorta) easily call external commands. fun times :) --- ¹ slightly more involved than a dumb code.replace('{', ':\n') because you need to maintain the indent level... but around that level of sophistication
deleted 6y ago
[deleted]
barbegal 6y ago
Definitely cheating, it's not autopilot. It is just updating your co-ordinates every 500ms on a straight line. I would like to see a real autopilot written in javascript that you can paste into the console.
- GistNoesis 6y ago
  It's cheating but not as much. It's setting the "motion vector" aka setting the speed at current instant. It's just skipping the controls which are normally setting the "motion vector". For the orientation it's totally cheating though using camera.lookat(target).
- zlsa 6y ago
  I wrote an autopilot[0] for the simulator in JS, which sends key events to the game. [0]: https://gist.github.com/ForestKatsch/01069f29e8316df117740258313665f1 https://gist.github.com/ForestKatsch/01069f29e8316df11774025...
  - jcims 6y ago
    This is awesome! As a recent student of PIDs, it's even better after uncommenting the createPidDisplay statement on line 566 :) Only feature request is a 'Do a Barrel Roll!' button.
xaedes 6y ago
Very simple P-controller based autopilot derived from the one-liner: let a = setInterval(() => { // retrieve values from simulation let roll = fixedRotationZ; let pitch = fixedRotationX; let yaw = fixedRotationY; let rpy = new THREE.Vector3(roll, pitch, yaw); let rollRate = -rateRotationZ/10.0; let pitchRate = -rateRotationX/10.0; let yawRate = -rateRotationY/10.0; let rpyRate = new THREE.Vector3(rollRate, pitchRate, yawRate); let pos = camera.position.clone(); let posRate = motionVector.clone(); let targetPos = issObject.position.clone(); let targetRpy = new THREE.Vector3(0,0,0); let dRpy = targetRpy.clone().sub(rpy); // P-controller controls target roll,pitch,yaw-rate (targetRpyRate) to reach target orientation let targetRpyRate = new THREE.Vector3( dRpy.x/1.0, dRpy.y/1.0, dRpy.z/1.0 ); let minRpyRate = new THREE.Vector3(-1.5, -1.5, -1.5); let maxRpyRate = new THREE.Vector3(+1.5, +1.5, +1.5); targetRpyRate.clamp(minRpyRate, maxRpyRate) let dRpyRate = targetRpyRate.clone().sub(rpyRate); // don't calculate with displayed x,y,z but the internal coordinates // (z-axis is forward and backward) let dPos = targetPos.clone().sub(pos); let d = dPos.length(); // P-controller controls target motion (targetPosRate) to reach target position let targetPosRate = new THREE.Vector3( dPos.x / 100.0, dPos.y / 100.0, dPos.z / 100.0 ); let minPosRate = new THREE.Vector3(-0.1, -0.1, -0.01); let maxPosRate = new THREE.Vector3(+0.1, +0.1, +0.01); // thresholds for bang contRol let dRpyRateControlThreshold = new THREE.Vector3(0.0, 0.0, 0.0); let dPosRateControlThreshold = new THREE.Vector3(0.001, 0.001, 0.001); // define some phases where we want to have different movement behaviour if (dRpyRate.length() > 0.1) { // not correctly oriented, stop movement targetPosRate.x = 0; targetPosRate.y = 0; targetPosRate.z = 0; } else if (Math.abs(dPos.z) < 20) { // we are very close, slow approach, larger P-control in lateral // directions to correct remaining errors minPosRate.z = -0.005; maxPosRate.z = +0.005; dPosRateControlThreshold.x = 0.01; dPosRateControlThreshold.y = 0.01; targetPosRate.x = dPos.x; targetPosRate.y = dPos.y; } else if (Math.abs(dPos.z) < 50) { // we are getting, close, slow down minPosRate.z = -0.01; maxPosRate.z = +0.01; minPosRate.x = -0.01; minPosRate.y = -0.01; maxPosRate.x = +0.01; maxPosRate.y = +0.01; } else if (Math.abs(dPos.z) < 100) { // slow down minPosRate.z = -0.1; maxPosRate.z = +0.1; } else if ((Math.abs(dPos.x) < 0.05) && (Math.abs(dPos.y) < 0.05)) { // lateral position correct, use maximum approaching speed minPosRate.z = -0.2; maxPosRate.z = +0.2; } targetPosRate.clamp(minPosRate, maxPosRate); let dPosRate = targetPosRate.clone().sub(posRate); // bang control to reach target roll pitch and yaw rate if (dRpyRate.x < -dRpyRateControlThreshold.x) rollRight(); else if (dRpyRate.x > +dRpyRateControlThreshold.x) rollLeft(); if (dRpyRate.y < -dRpyRateControlThreshold.y) pitchDown(); else if (dRpyRate.y > +dRpyRateControlThreshold.y) pitchUp(); if (dRpyRate.z < -dRpyRateControlThreshold.z) yawRight(); else if (dRpyRate.z > +dRpyRateControlThreshold.z) yawLeft(); // bang control to reach target motion if (dPosRate.x < -dPosRateControlThreshold.x) translateLeft(); else if (dPosRate.x > +dPosRateControlThreshold.x) translateRight(); if (dPosRate.y < -dPosRateControlThreshold.y) translateDown(); else if (dPosRate.y > +dPosRateControlThreshold.y) translateUp(); if (dPosRate.z < -dPosRateControlThreshold.z) translateForward(); else if (dPosRate.z > +dPosRateControlThreshold.z) translateBackward(); },100);

https://www.reddit.com/r/spacex/comments/gigmfh/spacex_iss_docking_simulator/fqfzatb/ https://www.reddit.com/r/spacex/comments/gigmfh/spacex_iss_d... does it in one line but it's kind of cheating.

Eduardo3rd 6y ago

browser console is a pretty under rated feature. I wish it was used more extensively to teach people how to code. so many cool little hacks you can do on public web pages that cement new concepts quickly.

yreg 6y ago

Anything is a oneliner when you erase all the `\n`s

jylam 6y ago
Python begs to differ
- vulcan01 6y ago
  You can add semicolons at the end of python lines to replace \n's when calling from the command line. python3 -c "n=1;print(n)"
  - pferde 6y ago
    How does it deal with code blocks normally defined by indentation? (As an aside, indentation being part of syntax is the only thing keeping me disgusted with python - I like the language otherwise.)
    - uryga 6y ago
      it doesn't :) though it works fine if your terminal allows multiline input: python -c " for x in stuff: this(x) that(x) " at some point i even wrote a hacky little wrapper that let you use braces and replaced¹ them with spaces+newlines, something like this: pyc-wrap "for x in stuff { this(x); that(x); }" i can dig the code up if you need it :) ======== though after that i sort of went of the deep end adding perl-style "it" ($_) variables for loop variables: for stuff { this($); that($); (yes, closing braces at the end were optional...) and for the result of the previous line: 2; $+1; hex($); # roughly translates to: x = 2; x = x+1; x = hex(x); surprisingly pleasant to use for shell-like tasks actually! edit: almost forgot - if during execution you used a name `foo` not found in locals/globals, `foo` was treated as an external command, and resolved to something like lambda *args: os.system('foo', *args) so that you could (sorta) easily call external commands. fun times :) --- ¹ slightly more involved than a dumb code.replace('{', ':\n') because you need to maintain the indent level... but around that level of sophistication

deleted 6y ago

[deleted]

barbegal 6y ago

Definitely cheating, it's not autopilot. It is just updating your co-ordinates every 500ms on a straight line. I would like to see a real autopilot written in javascript that you can paste into the console.

GistNoesis 6y ago
It's cheating but not as much. It's setting the "motion vector" aka setting the speed at current instant. It's just skipping the controls which are normally setting the "motion vector". For the orientation it's totally cheating though using camera.lookat(target).
zlsa 6y ago
I wrote an autopilot[0] for the simulator in JS, which sends key events to the game. [0]: https://gist.github.com/ForestKatsch/01069f29e8316df117740258313665f1 https://gist.github.com/ForestKatsch/01069f29e8316df11774025...
- jcims 6y ago
  This is awesome! As a recent student of PIDs, it's even better after uncommenting the createPidDisplay statement on line 566 :) Only feature request is a 'Do a Barrel Roll!' button.

xaedes 6y ago

Very simple P-controller based autopilot derived from the one-liner: let a = setInterval(() => { // retrieve values from simulation let roll = fixedRotationZ; let pitch = fixedRotationX; let yaw = fixedRotationY; let rpy = new THREE.Vector3(roll, pitch, yaw); let rollRate = -rateRotationZ/10.0; let pitchRate = -rateRotationX/10.0; let yawRate = -rateRotationY/10.0; let rpyRate = new THREE.Vector3(rollRate, pitchRate, yawRate); let pos = camera.position.clone(); let posRate = motionVector.clone(); let targetPos = issObject.position.clone(); let targetRpy = new THREE.Vector3(0,0,0); let dRpy = targetRpy.clone().sub(rpy); // P-controller controls target roll,pitch,yaw-rate (targetRpyRate) to reach target orientation let targetRpyRate = new THREE.Vector3( dRpy.x/1.0, dRpy.y/1.0, dRpy.z/1.0 ); let minRpyRate = new THREE.Vector3(-1.5, -1.5, -1.5); let maxRpyRate = new THREE.Vector3(+1.5, +1.5, +1.5); targetRpyRate.clamp(minRpyRate, maxRpyRate) let dRpyRate = targetRpyRate.clone().sub(rpyRate); // don't calculate with displayed x,y,z but the internal coordinates // (z-axis is forward and backward) let dPos = targetPos.clone().sub(pos); let d = dPos.length(); // P-controller controls target motion (targetPosRate) to reach target position let targetPosRate = new THREE.Vector3( dPos.x / 100.0, dPos.y / 100.0, dPos.z / 100.0 ); let minPosRate = new THREE.Vector3(-0.1, -0.1, -0.01); let maxPosRate = new THREE.Vector3(+0.1, +0.1, +0.01); // thresholds for bang contRol let dRpyRateControlThreshold = new THREE.Vector3(0.0, 0.0, 0.0); let dPosRateControlThreshold = new THREE.Vector3(0.001, 0.001, 0.001); // define some phases where we want to have different movement behaviour if (dRpyRate.length() > 0.1) { // not correctly oriented, stop movement targetPosRate.x = 0; targetPosRate.y = 0; targetPosRate.z = 0; } else if (Math.abs(dPos.z) < 20) { // we are very close, slow approach, larger P-control in lateral // directions to correct remaining errors minPosRate.z = -0.005; maxPosRate.z = +0.005; dPosRateControlThreshold.x = 0.01; dPosRateControlThreshold.y = 0.01; targetPosRate.x = dPos.x; targetPosRate.y = dPos.y; } else if (Math.abs(dPos.z) < 50) { // we are getting, close, slow down minPosRate.z = -0.01; maxPosRate.z = +0.01; minPosRate.x = -0.01; minPosRate.y = -0.01; maxPosRate.x = +0.01; maxPosRate.y = +0.01; } else if (Math.abs(dPos.z) < 100) { // slow down minPosRate.z = -0.1; maxPosRate.z = +0.1; } else if ((Math.abs(dPos.x) < 0.05) && (Math.abs(dPos.y) < 0.05)) { // lateral position correct, use maximum approaching speed minPosRate.z = -0.2; maxPosRate.z = +0.2; } targetPosRate.clamp(minPosRate, maxPosRate); let dPosRate = targetPosRate.clone().sub(posRate); // bang control to reach target roll pitch and yaw rate if (dRpyRate.x < -dRpyRateControlThreshold.x) rollRight(); else if (dRpyRate.x > +dRpyRateControlThreshold.x) rollLeft(); if (dRpyRate.y < -dRpyRateControlThreshold.y) pitchDown(); else if (dRpyRate.y > +dRpyRateControlThreshold.y) pitchUp(); if (dRpyRate.z < -dRpyRateControlThreshold.z) yawRight(); else if (dRpyRate.z > +dRpyRateControlThreshold.z) yawLeft(); // bang control to reach target motion if (dPosRate.x < -dPosRateControlThreshold.x) translateLeft(); else if (dPosRate.x > +dPosRateControlThreshold.x) translateRight(); if (dPosRate.y < -dPosRateControlThreshold.y) translateDown(); else if (dPosRate.y > +dPosRateControlThreshold.y) translateUp(); if (dPosRate.z < -dPosRateControlThreshold.z) translateForward(); else if (dPosRate.z > +dPosRateControlThreshold.z) translateBackward(); },100);