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← Homework 8 02 State Space Answermp4

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Showing Revision 4 created 05/24/2016 by Udacity Robot.

  1. And the answer is 2, 3, 4, 6, and 9.
  2. On the ground, the static state without velocity is just X and Y.
  3. That's 2.
  4. If we add mid-air, we have height, which adds a third dimension, 3.
  5. If we add the dynamic state to the ground,
  6. which is delta X and delta Y over time, that's 4 in total
  7. plus the original X and Y.
  8. Same for mid-air. Multiply 3 up to 6.
  9. And the last one is the tricky one.
  10. Clearly, a helicopter in mid-air
  11. that looks at rotational velocities would have 12 dimensions.
  12. But again, because I don't care about the absolute coordinates
  13. of its yaw, roll and pitch.
  14. The ball is variant.
  15. The spin variables are 3, delta roll, delta pitch and delta yaw.
  16. If we add those to the dynamic state in mid-air,
  17. we get 9 and not 12.
  18. Once again, these are X, Y and Z: delta X, delta Y, delta Z over time,
  19. and the velocities in the different rotational directions,
  20. which make a total of 9.