Beautiful robot xylophone build from reader David Watson. Campanello uses a set of eight bar chimes and resonators from a child’s set, fabricated wooden mallets, and some simple right-angle brackets designed by David and printed through Shapeways. Of the actuators themselves, David writes:
I was inspired by the Solar Xylophone in Make Volume 12. The Solar Xylophone uses geared pager motors in almost exactly the same application I was trying to produce. These motors had several things going for them. First, they were small and clearly didn’t require a lot of power. They also included an arm with a spring that returns the arm back to a neutral position after they’re turned off. The biggest thing I was concerned about was how hard it would be to adjust them to be consistent across all the bells. In the Solar Xylophone application, there is lots of hand tuning to get the balace of the mallets just right. In the end, the motors worked out perfectly. I was able to find a configuration that was relatively easy to replicate without hand tuning. The variance I did end up with was easy to fix in software, and would be easy to eliminate with better manufacturing techniques.