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Open-Loop vs Closed-Loop Descent Guidance

Two landers descend toward the same pad under the same wind gust and sensor noise. The open-loop one flies a pre-computed thrust plan and never corrects; the closed-loop one continuously measures its position and steers back. Watch a live position-error chart for both.

Space & Astronomy3DModerate60 FPS💨 Air & Wind

Two identical landers begin powered descent from the same position under the same wind gust and sensor/actuator noise. The open-loop lander flies the exact thrust plan it computed before the descent began and never re-checks where it actually is. The closed-loop lander continuously measures its own position and corrects its thrust in real time. Watch the live position-error chart diverge between the two, then run repeated randomized descents to compare touchdown accuracy.

⚙ Under the hood

Two identical landers begin powered descent from the same position under the same wind gust and sensor/actuator noise. The open-loop lander flies the exact pre-computed thrust plan and never re-checks where it actually is, drifting progressively off-target. The closed-loop lander continuously measures its own position and corrects its thrust in real time, steering back toward the pad. A live position-error chart compares both modes, with a running touchdown-accuracy tally.

guidance and controlclosed-loop controlopen-loop controlpowered descentfeedback guidanceThree.js

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