This is a simple two micro-servo and Arduino Uno controlled drum machine or robot. The servos are mounted on an L-shaped bracket of wood that is held to the snare drum with 4 strong magnets. The servo arms are bolted to two chopsticks which serve as the drum-sticks. It is quite loud but not too loud. Much louder hits could be obtained by using standard size servos and real drum-sticks which are quite a bit heavier. But that would also require a separate power supply for the servos. By using micro-servos the Arduino supplies enough current to power them directly without a separate power supply.
The video shows my attempt at programming a simple version of the Wipeout drum solo. Of course it is not at the real 160 beats per minute but that could easily be obtained by adding another servo which would be pretty cool. I haven’t calculated what the top bpm that can be obtained by using a servo and it does require some delay in getting the drumstick from its parked position to the drum-head.
The rhythms you can create are only limited by your imagination and the drum machine is a more interesting companion to play with than a digital drum machine, if you are a musician.
The only downside is the servo noise which isn’t really that noticeable though the camera audio seems to pick it up quite notably.”

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