About Ringer

What is a church bell simulator?

An English church bell is rung by swinging the bell through a full circle, from mouth-up to mouth-up. As the bell swings, the clapper swings from one side to the other, and when it hits the bell it makes a (very loud) noise. One of the problems of ringing is how to get plenty of practise in without annoying your neighbours. To do this, a simulator is used.

To use a simulator, first a large piece of rubber is wrapped around the clapper so that it doesn't make any noise. A sensor is attached to the bell (usually on the wheel) to detect the motion of the bell. When the bell reaches the right point, the sensor triggers a computer to make a sound like a bell.

Simulators are used for practising with a full band but without annoying the neighbours, for training new ringers and for filling in for a band when there are only one or two ringers practising.

What's wrong with the simulators that are out there?

Simulators have been used for years now and are reasonably successful. They are good and useful as far as they go. But in my opinion they lack ambition.

Most simulators in use in towers today use sensors that produce pulses when the bell passes a certain point, usually either one or two per revolution. The sound is then produced a fixed time after this pulse. That is good enough when the bell is up, but it all gets rather messy when ringing up or ringing down.

Simulators in use today require a desktop computer to drive them and make a positively evil misuse of a computer serial port as a GPIO (general-purpose input/output) interface.

When using one of the common simulators, the only usable feedback to the ringers is the sound of the bell. This is good for developing rhythm and ringing by ear, but most ringers will usually use sight as the main input to decide when to pull.

The only inputs to simulators are a mouse, keyboard and sometimes a three-channel footswitch for 'calling' touches and so on.

How will Ringer be different?

Ringer will improve on current simulators in the following ways:

• It will use a much higher-resolution sensor on the bell to track bell motion right through the swing and accurately model when the clapper hits the bell. This will allow accurate simulation even with the bell almost entirely down.
• It will use a cheap off-the-shelf single board computer (probably a Raspberry Pi). The whole system should be usable with just this computer, but can be expanded with others. This provides a better way to interface to sensors, as well as avoiding the need to scrounge old computers.
• When the simulator is being used to 'fill in' missing ringers, it will provide a display of what those ringers are doing.
• It will provide a graphical display of what the bells are doing while they are being rung.
• It will respond to voice commands, allowing called changes, touches and so on to be called as with an ordinary band.
• It will also emulate the RS-232 interface used on other simulators so that it can be used as an input to them.