Compound Pendulums

Team members: 陳盈珊 李思杰

Goal

We use a setup to realize two physics phenomenon

1. flipping of lower pendulum in double pendulum
2. the synchronization of two single pendulems on a plane with wheels.

Measurement Method

Use image analysis to track specific point on the pendulum. Record 10 to 15 frames per second.

Anaylsis Method

1. Time series observation
2. Energy transfer
3. Phse diagram

Flipping Pendulum

What does flipping means?

Non-flipping with initial condition \( \theta_1=\theta_2=60^\circ\)

Flipping with initial condition \( \theta_1=\theta_2=90^\circ\)

When will flipping happen?

The figures here are generated by simulating double pendulum motion.

Experimental setup

Experimental result

Conclusion

1. Observing pendulum flipping from energy view.
2. Flipping may be delayed for long time, even total energy is enough.

Synchronized pendulum

Experimental setup

Experimental result

Conclusion

1. Pendulum phase alternatively leads and lags.
2. Energy transfer between two pendulums is related the phases.
3. Motion of basis is determined by phases.