Another Arduino-controlled pendulum clock

It's very interesting to see this thread burst into life again after a couple of years.
My own developments over the last couple of years have been to greatly simplify the control of the wooden clock. It now uses an Arduino which makes experimenting much easier and allows me to include my interest in writing software in this project.

The original design had three magnets on the rim of the pendulum and a hall sensor on the frame so that measuring the delay between them passing the sensor could measure the linear velocity of the pendulum which is related to the amplitude of the swing. This becomes unnecessary in the new design, who's software has become simpler and simpler over time as I realised what is, and is not, necessary for good control of the clock.

The basic control is as described in my earlier post but the software parameters can more easily be altered to suit the mechanics of the clock and it's response time and variation around exact timing. The Arduino proves a serial output of the pendulum period and relative timing to the 1PPS pulses which is interesting and allows easy fine tuning of the pendulum weight and software parameters. Once settled, the period drifts around +- 5mS and the timing relative to the 1PPS varies about +- 20mS.

My clock is all wood and the mechanism is driven by the pendulum rather than the other way round in more traditional designs, but the basic measurement principle could be used to regulate many types of clock by suitable means.

I know some people consider locking a pendulum to a crystal as 'cheating' but we make these machines as a hobby, don't we? Something for our own amusement, designed to exercise our minds and utilise the particular range of knowledge and skills we have each acquired. It's only cheating if you misrepresent your creation as something it is not by, for example, entering it in a competition for purely mechanically timed machines.

A more reecnt version of the design can be seen at the link below. I'm currently working on a bigger version made from Tasmanian hardwoods.
https://vimeo.com/614929644