Making Rockets Hover with PID Controllers

It’s not rocket science, it’s control theory

SpaceX Dragon 2 hovers a few feet above the ground.

Playing God — Simulating Physics

Idealized rocket dynamics.
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Full speed ahead.

Aside: Integration

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Left: We can exactly compute the acceleration integral by using small rectangles. Right: We cannot exactly compute the velocity integral using the same method.

Control

On-Off Control

The On-Off controller.
Sketch of how to run the simulation.
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The On-Off controller causes wild oscillations around the target.

PID Control

The PID controller.
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Near optimal control with the PID controller.

Conclusion

Machine Learning at Facebook AI. Previously at Google Research.

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