Slow motion bellringing - with animation
Ringing the 5th at St John's Cathedral, Brisbane. Filmed at 200 fps on a Panasonic DMC-ZX200. The animation shows the position of the bell, taken from a sensor attached to the wheel.
The sensor consists of an accelerometer and a gyroscope, which is filtered to produce estimates of the angle of the bell, the velocity, and force applied to the rope. The clapper position is simulated using the equations of motion of a coupled pendulum. I guessed various physical parameters in the simulation, including the weight and length of the clapper, and the position of the garter hole.
There are a few times where the animation is a bit jerky. This is because it is designed for real-time output, and between sensor measurements it extrapolates the position of the bell. Sometimes the extrapolated position isn't exactly where the bell turns out to be when the next sensor measurements arrive.
Please ignore the small problem of the clapper position not always clipping properly at the side of the bell, that is a bug in the software that I hadn't noticed until watching it in slow motion!
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Awsome video! Having the animation exactly in sync with the video of the ringer makes it so clear what is going on up in the belfry, including the motion of the clapper and why the strike occurs when it does. Good idea and well done! Thanks for posting.
Thank you so much for this video. I've been watching many videos on bell ringing and find them very interesting. But whether watching the ringing bells or bellringers, I could not understand why the ropes were 'bouncing'. Your animation side by side with the bellringer explains it better than any words might have. TY!
I’ve only been ringing a short time but also enjoy understanding the mechanics of the bell tower and I’ve been up in our churches many times. I would agree that the clapper does not behave the way shown in the video. The clapper moves faster than the bell and strikes the side opposite to it’s rest position when the bell is approximately horizontal as it swings up. The clapper rebounds very very slightly which allows the bell to ring (speak) the clapper then follows the bell and comes to rest gently against the bell. If the video was correct the bell would never speak properly as the clapper would muffle the sound. If the bell did actually speak at the very end of the sally and tail stroke the timing would be so much easier but as we ringers know, it isn’t. The bell speaks before you have completed the tail end stroke and after the sally has passed your face on the way up on the sally stroke.
Just a thought...it would be interesting to create a similar video with a bell that is odd-struck, so we can see how and why that happens as well.
wow
Dear Brisbane Ringers. I am preparing a presentation designed to help recruit ringers to my home tower in Brewood, Staffs, UK. I would like to include a short clip from this excellent video. Is that OK with you ? Regards. Steve Askew
I’ve just started bell ringing (only one lesson) and I found that the amplitude of my hand positions, from highest to lowest, was much less than your video (and a lot of other videos) show. I seemed to be raising my hands only to my forehead on the upstroke (both handstroke and backstroke) and to roughly my belt on the downstroke (both on handstroke and backstroke). I’m guessing that the amplitude must vary with the diameter of the wheel, and where the rope is attached to the wheel. I certainly wasn’t stretching anywhere as high as the person in your video is doing. Any help would be appreciated.
Do you have animation videos of raising and lowering a bell ?