The Returning Rocket Friend or Foe? David Franklin & Philip - - PowerPoint PPT Presentation

The Returning Rocket

Friend or Foe? David Franklin & Philip Massey

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The Returning Rocket - David Franklin & Philip Massey

Outline

• Introduction

○ Motivation ○ Safety ○ Physics

• Controllers

○ Strategy ○ Descent ○ Balance

• Conclusion

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The Returning Rocket - David Franklin & Philip Massey

Outline

• Introduction

○ Motivation ○ Safety ○ Physics

• Controllers

○ Strategy ○ Descent ○ Balance

• Conclusion

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The Returning Rocket - David Franklin & Philip Massey

Introduction

How do we make space exploration less expensive? Possible answer:

• Reusability of launch

vehicles

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"Atlas EELV Family" Public Domain, US Gov FFA

The Returning Rocket - David Franklin & Philip Massey

Introduction - Problem

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http://youtu.be/0UjWqQPWmsY?t=40s

The Returning Rocket - David Franklin & Philip Massey

Introduction - Safety

• Descent

○ Must land with safe velocity

• Balance

○ Maintain a safe rotation

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"Falcon rocket family" by Craigboy - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons

The Returning Rocket - David Franklin & Philip Massey

Introduction - Physics

• Descent

○

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The Returning Rocket - David Franklin & Philip Massey

Introduction - Physics

• Descent

○

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The Returning Rocket - David Franklin & Philip Massey

Introduction - Physics

• Descent

○

• Balance

○

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The Returning Rocket - David Franklin & Philip Massey

Outline

• Introduction

○ Motivation ○ Safety ○ Physics

• Controllers

○ Strategy ○ Descent ○ Balance

• Conclusion

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The Returning Rocket - David Franklin & Philip Massey

Controllers - Strategy

• Use two time-based controllers

○ One controller for descent ○ One controller for balance ○ Either can be changed without need to reprove

• ther controller.

○ Cannot take advantage of particular descent strategy.

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The Returning Rocket - David Franklin & Philip Massey

Controllers - Descent

• Safety:

○ At height h = 0, ensure v < vsafe

• Cased solution:

○ If speed greater than max: ■ ○ Else if speed less than max and can free fall: ■ ○ Else: ■

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The Returning Rocket - David Franklin & Philip Massey

Controllers - Balance

• Safety:

○ Maintain a bound on rotation

• Idea:

○ Non-deterministically assign

• Simple Solution:

○ Set ○ Keep ○ Use

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The Returning Rocket - David Franklin & Philip Massey

Conclusion

• Safety
• Physics
• Controllers

○ Strategy ○ Descent ○ Balance

• Importance

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"SpaceX Landing Rendering" Jon Rosszlsa

The Returning Rocket - David Franklin & Philip Massey

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Questions?