kerbal_space_program.rb

So there's this game, Kerbal Space Program. You basically create your own space program from scratch. Well, you can control it via TCP, and—using Ruby—we're gonna launch, orbit, and crash our brave Kerbins. You might even learn a thing or two about orbital mechanics and control theory along the way.

Transcript

1. > kerbal_space_program.rb ~brad_grzesiak/keep_ruby_weird | 2017-10-27 14:30 ~brad_grzesiak/keep_ruby_weird | 2017-10-27 14:29 > groups brad_grzesiak wheel bendyworks twitter.listrophy
2. Whenever Brad is drinking, you wanna make sure you're sitting next to him, because instead of being obnoxious, he teaches you orbital mechanics. Ashe Dryden
3. Whenever Brad is drinking, you wanna make sure you're sitting next to him, because instead of being obnoxious, he teaches you orbital mechanics. Ashe Dryden GET YOUR ALTERCONF TICKETS!
4. PREFACE PREREQUISITES
5. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam)
6. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam) $24
7. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam) ▸ Install ckan $24
8. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam) ▸ Install ckan ▸ Install kRPC on ckan $24
9. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam) ▸ Install ckan ▸ Install kRPC on ckan ▸ EMA 550: Astrodynamics $24
10. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam) ▸ Install ckan ▸ Install kRPC on ckan ▸ EMA 550: Astrodynamics ▸ ME 446: Automatic Controls $24
11. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam) ▸ Install ckan ▸ Install kRPC on ckan ▸ EMA 550: Astrodynamics ▸ ME 446: Automatic Controls ▸ Install ruby correctly #%&! $24
12. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam) ▸ Install ckan ▸ Install kRPC on ckan ▸ EMA 550: Astrodynamics ▸ ME 446: Automatic Controls ▸ Install ruby correctly #%&! ▸ gem install krpc $24
13. PREFACE PREREQUISITES ▸ Buy KSP ($40 on Steam) ▸ Install ckan ▸ Install kRPC on ckan ▸ EMA 550: Astrodynamics ▸ ME 446: Automatic Controls ▸ Install ruby correctly #%&! ▸ gem install krpc ▸ Write some ruby $24
14. SPACE.FAIL:3000
15. PROJECT 1: MERCURY HOVER
16. MAKE A ROCKET HOVER PROBLEM STATEMENT:
17. MAKE A ROCKET HOVER PROBLEM STATEMENT: MAKE ALTITUDE CONSTANT (AND SUFFICIENTLY >0)
18. MAKE A ROCKET HOVER PROBLEM STATEMENT: MAKE ALTITUDE CONSTANT (AND SUFFICIENTLY >0) 1 CONTROL: THROTTLE (ALSO, VARIABLE MASS)
19. PROJECT 1: MERCURY SOME MATHS F = m⋅a ∑ T − m⋅ g = m⋅a T − m⋅ g = m⋅ d dt v T − m⋅ g = m⋅ d2 dt2 x T(t) − m(t)⋅ g = m(t)⋅ d2 dt2 x(t)
20. PROJECT 1: MERCURY SOME MATHS F = m⋅a ∑ T − m⋅ g = m⋅a T − m⋅ g = m⋅ d dt v T − m⋅ g = m⋅ d2 dt2 x T(t) − m(t)⋅ g = m(t)⋅ d2 dt2 x(t) Nonlinear 2nd Order
 Differential Equation
21. PROJECT 1: MERCURY SOME MATHS F = m⋅a ∑ T − m⋅ g = m⋅a T − m⋅ g = m⋅ d dt v T − m⋅ g = m⋅ d2 dt2 x T(t) − m(t)⋅ g = m(t)⋅ d2 dt2 x(t) Nonlinear 2nd Order
 Differential Equation ಠ_ಠ
22. PID CONTROLLER
23. P I D CONTROLLER roportional ntegral erivative
24. P I D CONTROLLER roportional ntegral erivative
25. PROJECT 1: MERCURY NEGATIVE FEEDBACK THROTTLE
26. PROJECT 1: MERCURY NEGATIVE FEEDBACK THROTTLE ROCKET
27. PROJECT 1: MERCURY NEGATIVE FEEDBACK ACTUAL ALTITUDE THROTTLE ROCKET
28. PROJECT 1: MERCURY NEGATIVE FEEDBACK ACTUAL ALTITUDE THROTTLE ROCKET PID CONTROLLER DESIRED ALTITUDE
29. PROJECT 1: MERCURY NEGATIVE FEEDBACK ACTUAL ALTITUDE THROTTLE ROCKET PID CONTROLLER DESIRED ALTITUDE
30. PROJECT 1: MERCURY PID CONTROLLER prev_time = Time.now dt = 0.1 prev_error = 0 accumulated_error = 0 while true do sleep dt curr_time = Time.now error = DESIRED_ALTITUDE - current_altitude() accumulated_error += error * dt derivative = (error - prev_error) / dt set_throttle( P * error + I * accumulated_error + D * derivative ) prev_error, prev_time = error, curr_time end
31. DEMO
32. PROJECT 2: GEMINI ORBIT Photo courtesy of: SpaceX
33. MAKE A ROCKET ORBIT PROBLEM STATEMENT:
34. MAKE A ROCKET ORBIT PROBLEM STATEMENT: GO REAL HIGH, THEN ON THE WAY BACK DOWN, MISS
35. OUR ROCKET
36. First Stage OUR ROCKET
37. OUR ROCKET Second Stage }
38. OUR ROCKET Third Stage }
39. ORBIT?
40. ORBIT?
41. ORBIT?
42. ORBIT?
43. ORBIT?
44. ORBIT?
45. ORBIT? 1 foot Austin Houston
46. ORBIT? 1 foot Austin Houston d = 237km
47. ORBIT? 1 foot Austin Houston d = 237km h = 4.41km
48. ORBIT? 1 foot Austin Houston d = 237km h = 4.41km t = 30s
49. ORBIT? 1 foot Austin Houston d = 237km h = 4.41km t = 30s v = 7.9km/s
50. ENERGIES
51. ENERGIES Get up there m g h = E g h = E/m (9.81/1000) 200 1.96 MJ
52. ENERGIES Get up there m g h = E g h = E/m (9.81/1000) 200 1.96 MJ Go real fast E = ½ m v2 E/m = ½ v2 ½ (7.8)2 30.4 MJ
53. PROJECT 2: GEMINI OK, BUT HOW? ▸ Checklist! ▸ 2 state machines: staging & control ▸ On each tick, use case-when for each state machine ▸ On each state-transition, maybe do a single thing ▸ "Pitch over while managing stages"
54. DEMO
55. PROJECT 3: APOLLO TO THE MUN!
56. LAND A ROCKET ON THE MUN PROBLEM STATEMENT:
57. LAND A ROCKET ON THE MUN PROBLEM STATEMENT: LANDING SPEED UNSPECIFIED; LEFT TO DEVELOPER
58. ORBIT TRANSFERS
59. ORBIT TRANSFERS
60. ORBIT TRANSFERS
61. ORBIT TRANSFERS
62. TO THE MUN
63. TO THE MUN
64. PROJECT 3: APOLLO STATES 1. determining insertion burn delta v 2. determining insertion burn location 3. waiting for insertion burn far 4. waiting for insertion burn mid 5. waiting for insertion burn near 6. insertion burning 7. finalizing insertion burn 8. transmunar orbit 9. outer munar orbit 10.mid munar orbit 11.final approach
65. DEMO
66. THANK YOU! Brad Grzesiak - @listrophy CEO, Bendyworks