Kyklophonon'

Check out this "Physical Sequencer" as described by it's maker Michalis Shammas ! 
In his own words:
'It consists out of strings with suspended weights that are free to slide on pulleys to enable a continuous frequency spectrum.
You can use a simple "actuator" system to automate the instrument like a sequencer.
Everything is amplified with piezoelements. It is a work in progress.'
More info Here:
https://michalisshammas.com/Work