Balancing Act

Keeping a stick upright

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• An inverted pendulum is unstable: tilt grows unless corrected.
• PD control stabilises it if K_p beats gravity; K_d damps the wobble.
• Shorter sticks fall faster (time scale √(L/g)), so delays matter more.

Steps

1. Unstable on its own
2. Keep it up
3. The minimum push
4. Broom or pencil?
5. Rockets on their tails
6. What if the hand is slow?