• John de Overa
    72
    A while ago there were some attempts to monitor the rope forces during ringing, but I haven't heard anything about it for quite a while. Were there any results and conclusions?
  • John Harrison
    92
    I wrote the last progress update for the RW in December 2019. CoViD disrupted things but there has been further work since then, and I am currently in correspondence with developers.
  • John de Overa
    72
    I was wondering if it had provided definitive proof that pulling harder doesn't make the bell go any faster...
  • John Harrison
    92
    the effort is going into making the technology work properly, ie making sure that the measurements reflect the real forces under different conditions,which is harder than you might imagine. Also, trying to get a system that can be cheap enough to encourage widespread use.
    As for your question, it would need to be more precise about what is meant by'pulling harder' and 'going faster'.
  • Nigel Goodship
    8
    The ultimate pullometer:

    https://www.opusds.com/bellsim

    Trouble is, there's only of them. And, I suppose, because the relationship between rope tension and bell speed is programmed, it can't really answer the question of how much, if any, pulling harder while the rope is moving downwards makes that same stroke ring any sooner on a real bell. However, it's a fantastic tool for measuring the tension in the rope during the entire ringing cycle for each stroke. See:

    https://www.opusds.com/bellsim-images-traces?pgid=kxa61cau-db59180a-3075-4a64-b407-952391ff33a3

    I'm immensely impressed with this device. What a fantastic teaching tool as well. Imagine being able to dial-down the force of gravity to slow the whole thing down at first and gradually work up to full speed. And the safety cut outs virtually eliminate the risk of injury.
  • Simon Linford
    152
    When I went up to see BellSim I experienced how it met the Pullometer brief, albeit in a very expensive way (and that's not all it does of course). On the setting where it gives a constant display of force on the rope you could practice being as efficient as possible and it was really good.
  • John de Overa
    72
    it would need to be more precise about what is meant by'pulling harder' and 'going faster'.John Harrison

    What I was pondering is if the pullometer could be used to persuade people that they don't need to be heaving on the rope to get the bell going faster. When learners are asked to ring faster they usually try to do so by pulling harder which usually means as a side-effect that they pull sooner as well. If my (limited) understanding of bell physics is correct It's the pulling sooner bit that speeds up the bell not the pulling harder bit, but people make the wrong assumption and try and pull the bell out of the tower to go faster.

    If would be interesting to confirm if the pull exerted by a skilled ringer wasn't that different between fast and slow.
  • John de Overa
    72
    Trouble is, there's only of them.Nigel Goodship

    Actually, not so. I've rung on a similar but simpler system. It's incredibly realistic, to the point where you can actually bounce the bell on the (non-existent) stay. The person who designed them is I believe creating a ring of 10.
  • Nigel Goodship
    8
    That sounds very interesting, do you have any details that it would be possible to share?
  • John de Overa
    72
    I'll ask, last time I talked to him he was still in "stealth mode", fine tuning the system. Mechanically it's quite simple, a motor and controller with a belt drive to a drum around which the rope is wrapped.
  • Nigel Goodship
    8
    It would be interesting to confirm if the pull exerted by a skilled ringer wasn't that different between fast and slow.John de Overa

    I'm sure this is true, and I'm also sure that Stephanie Pattenden or Julia Cater (and many others, of course ) would be able to confirm it. :-) But you're quite right that it would be very interesting to measure the forces accurately with both experienced and inexperienced ringers ringing the same thing.

    One of the reasons bells are hung the way they are is so that it is possible to change the speed with little effort. In very broad terms, at the point of the swing where speed adjustment is made, the bell is moving mostly horizontally and very little vertically, so the ringer mostly has to just tweak its momentum and not so much its potential energy. I.e. to go faster you cut short the bell's movement at the end of its swing and this only changes the peak "height" of the bell by a very small amount. And because the bell is moving slowly at the end of its swing when it's near the point of balance, you don't need to change the distance of its swing very much at all to make a significant difference to the timing of the swing.

    Talking of the physics, something to bear in mind when ringing is that Work Done = Force x Distance, so even if there's quite a bit of work to be done to remove energy from the bell (to make it ring quicker) or add energy (make it ring slower), this can still be achieved with a small force if that force is applied over a large distance. I think this is the main technique required for ringing with little effort, that and never letting the bell go significantly beyond the point of balance. Sorry, waffling on and straying off topic, but it's sort of related.
  • John de Overa
    72
    a small force if that force is applied over a large distance. I think this is the main technique required for ringing with little effortNigel Goodship

    I think that approach also makes it easier to be accurate, as if you aren't "snatching" at the rope you get better feedback.
  • Peter Sotheran
    32
    Some while ago, we used a device that measured the interval between a reflective strip passing a sensor and the moment the clapper strikes, to determine and any adjust odd-struckness in our bells. The job done, we experimented with our 2cwts treble and despite our best efforts we were unable to significantly alter the rotational speed of the bell by the application of brute force! The only way to make it ring more quickly was by shortening the stroke. Naturally, the heavier the bell, the less the effect of the brute force!
  • John de Overa
    72
    we were unable to significantly alter the rotational speed of the bell by the application of brute force!Peter Sotheran

    That was my guess of what would probably happen based upon the physics of simple pendulums, but bells aren't just simple pendulums. Thanks for the confirmation, physics wins again :grin:
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