Bell Ringing Mechanism

How about a large solonoid? Just don't act un-christian, like these guys.

To ring a bell, you pull the rope at the natural frequency of the bell pendulum. Then release on the back stroke.
One suggestion, use an air cylinder. Apply air to pull rope then retract. Fit it with exhaust valves to control speed and adjustable limits to control stroke. Use a PLC to fire the air solenoids and set the time between actions.
Second suggestion might not work but is much simpler. Attach a leverarm to a gear motor with adjustable speed. Set it to pull the rope at the natural harmonic frequency. For this to work, the motor is going to have to pull the rope quick enough that slack develops on the end of the pull stroke, allowing the leverarm to get back without tension on the rope. there might be an ingenious mechanism to deal with this issue.
Karl

A good engineer would study the process first...
Mark the rope with a scale and a timer behind it. Video it when ringing in steady state by hand just like you'd like it. Now watch the video frame by frame for time and position. With good data on where the puller needs to be vs. time a great simple mechanism should be easy to design.
Karl

Use a gear motor with a cam to quickly pull and release the rope (or cable). Select rpm of cam to suit frequency of chimes. A cam speed of 20 rpm would yield a chime every 3 seconds.
A heavy duty spring in the rope or cable might be necessary to allow the clapper to bounce, making the exact length of the rope or cable less critical.

Spring-return solenoid at the bell end, timing motor running simple cam and roller-micro-switch to make it go.

Why not call the last church bell manufacturing company in the US and order one in the size for your bell. They'll even show up and install it for a fee. They were on Dirty Jobs a couple years ago.
and here's the bell ringer page.
Karl

I forgot to say or look at them to get ideas and make your own. This youtube link shows one version and it's funny.

I would think about a solenoid in place of the clapper.
To actuate the solenoid, you could either design an electronic circuit or you could make a cam that runs on a gear reduction motor to trigger a switch.

Karl et al.
Thanks for the link. I also found some others that I will call Monday.
FWIW I did do a google search but apparently did not use the correct search words.
Thanks to all.
Take care Bob AZ