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HiMM
11-19-2017, 11:02 PM
Hello there!

I'm sure I'm in way over my head here but where else can you start?

I want to build a drummer robot similar to the one in the band Compressorhead. I know he is pneumatic with in line actuators in his arms and that's pretty much all I know about it. Where would I begin to build something like this? I have ideas about how to make him LOOK but not how to make it actually work. Is there any way to get a schematic of something like him? I've found information and have a tiny bit of knowledge about how an arm like his moves, but I'm clueless on how to make him strike the drums fast enough to mimic a real player and where to start running and operating him. Any advice you can give me would be great. Links, personal notes I can use, drawings or diagrams?

Thanks! !

jwatte
11-20-2017, 08:23 PM
First question: Do you want to use pneumatic actuators, or electromagnetic/motor actuators?
If you want to use pneumatics, you need to decide on a set of actuators (cylinders) and a tank/compressor system to go with it.
Then you can start doing math, based on the specifications of the actuators you select.
If the actuators can move X inches per second, and you attach them Y inches away from a fulcrum that the drum sticks rotate around, that will give you a calculation for how fast the drum stick can move in radians-per-second; multiply by radius and you get speed of movement of the actual stick head.

HiMM
11-21-2017, 01:37 AM
First question: Do you want to use pneumatic actuators, or electromagnetic/motor actuators?
If you want to use pneumatics, you need to decide on a set of actuators (cylinders) and a tank/compressor system to go with it.
Then you can start doing math, based on the specifications of the actuators you select.
If the actuators can move X inches per second, and you attach them Y inches away from a fulcrum that the drum sticks rotate around, that will give you a calculation for how fast the drum stick can move in radians-per-second; multiply by radius and you get speed of movement of the actual stick head.

Gotcha. Do you know what the pros and cons are for each system? Which would be more expensive? Where would you start looking for the parts? It SEEMS like pneumatic is the way to go, but I'm not certain.

Thanks again.

jwatte
11-21-2017, 10:15 PM
I've never built a pneumatic system, but I hear that once you get a few actuators, it's cheaper than electromechanical for a given power level.
The draw-back is that it's less precise, and perhaps noisier (compressor can be loud!)
For electromechanical parts, I'd look at the Robotis servos, because they are easy to work with and reasonably precise. The toy models (XL-320, AX-12A) may be enough for a reasonable drummer; if not, you'd need to upgrade to some of the more expensive ones (XM or MX series.)
For pneumatics, I don't know -- try mcmaster.com perhaps?