Hello Steve, I was wondering if you are familiar with a wooden clock designed by DickB called Synchonicity? Specifically, I am interested in the method of speed regulation by altering the pendulum swing amplitude. I have been tossing around doing something similar with your electo-magnetic pendulum design. With my lack of mechanical engineering and coding skills it might be difficult for me to pull off. But I'm sure I would learn something while trying even if I failed. I'm betting you are familiar with it but here is a link to an instructable just in case.
https://www.instructables.com/A-wood-gear-clock-with-a-unique-drive-mechanism/
Anyways I was just wondering if you had ever considered something along these lines to increase the accuracy of your electro-magnetic pendulum clock?
Yes, I have seen it and it is a great design. Any mechanism that calibrates the pendulum period is an improvement.
I searched through many different pendulum drive mechanisms and eventually settled on one that I considered to be the simplest to implement. The electronics in Dick's clock are fairly complicated but should be possible to incorporate into my clock. It would need a new base to hold everything. The algorithm would need to be adjusted to account for a different nominal pendulum period. It looks like he has a few different driver circuits posted to https://carveshop.com/electronics/
I did a few experiments using a microcontroller to adjust the clock period. It used an Arduino and an RC servo to tilt the table on a Congreve style clock. These designs are notoriously bad timekeepers, but the RC servo can easily change the tilt angle and adjust the rate. The design has only made it as far as a test bench for the track. It still needs an elegant solution for the end detection switches. The top end with all the gears should be easy. It is on my list of future projects.
Very cool! I didn't even know what a Congreve clock was but I do now, I would love to see your servo tilt experiment. I am not familiar with the microcontroller that DickB used but I have some experience with the Atmega and Arduino. For me the base redesign would be the easiest part. The pendulum and pawl arrangement would probably be the next challenge and for me at least the Arduino sketch would be the hardest. Right at the moment I am committed to finishing an SP2 for my daughter. Then I have a 3D printed RC VTOL project on the list. I have so many projects. I'd like to experiment with this idea and your clock but it may be awhile before I am able to get to it.
It's a good thing you are not in a hurry to build the Congreve clock. This is as far as the design has progressed. The tray 16" by 3.5". It doesn't look like a clock yet and I also have a lot of other projects lined up.
Figuring out a good tray design was a challenge. The important parts are in place. Specifically, small ramps on the ends and corners to prevent the ball from flying off. The tracks use over-rotation to slow them down compared to simply rolling down an incline plane. The concept is described here at 6m17s. https://youtu.be/M6T6CSiJv-A?t=377
That is awesome. Thanks for the pic!