Calliope, anybody?

Hi, I’m not sure that this was the best forum to place this, but I suppose an admin can move it if necessary. Our team (6065) is looking at making a promotional robot for sporting events and things, and we are looking at putting a t-shirt gun on it. The idea just sprang upon me today that another fun thing to try might be adding a calliope to the robot to play our school fight song. Thoughts on the calliope?

I’ll admit I had to look up what a Calliope is, but certainly seems like an interesting idea. Looks like you’d have to actually, you know, generate steam somehow. This seems like it would be a messy thing to deal with, especially since you’d then be out of the range of FIRST legal parts, which means just about everyone you’re dealing with is less experienced with such things. Assuming you got it electrically boiling, you’d also need a way of regulating the pressure evenly, otherwise bad things can happen. Also, you’d need to tune it. Either you’d get some pre made whistles, or you’re going to spend a LOT of time getting the right pitch for each. From there you’re either stuck in the key that your fight song is in, or you’re making a chromatic one, which takes even longer.

I think the idea of it playing music is cool, but I’m not sure a acoustic instrument is the correct way of going about. Perhaps attach a speaker, a MIDI sequencer and a Animusic style light show (with less CGI)? I think that get’s a bigger wow factor and is also easier on you, the people building the thing.

Combine the two build a Calliope T-shirt cannon

We considered an (air rather than steam) calliope for our air cannon a few years ago, and decided that with the number of pipes and controls needed, it was much simpler to go the electronic route. We found a device online (sparkfun?) that was essentially an MP3 player controlled over a serial line. Put that into a car stereo amplifier, and add speakers.

I think a robot calliope sounds like an awesome idea! It would definitely fit the steampunk theme of 2017. You could use air to play it, but it would have to be a fairly basic calliope and play a short song, because as others have said, it could get pretty complex. You’ll need a lot of air for it to work, but having a lot of tanks on the robot could pose a safety hazard. Maybe you could do it with fans?

Use compressed air instead of steam as it will be much easier and safer to work with. Buy a heap of cheap pneumatic solenoids from aliexpress and a high flow 12v air compressor and some air tanks. Run the solenoids over a relay bank using an arduino mega. This will be the cheapest way of building what you want.

I think it will be a fun activity trying to tune all the different pipe lengths.

Explanation needed as to why a lot of tanks on a robot is dangerous/ unsafe.

Also fans will not work, because of the significant spool up and spool down time of the blades. A solenoid is off-on-off quickly a fan is not off-on-off quickly at all.

But…the calliope crashed to the ground.

For COTS components/assemblies, here’s one candidate supplier to consider:

If you’re feeling spendy, they’d happily build the whole thing for you… otherwise, they’ll fab and sell any percentage of the hardware that you’re willing to pay for.

How about making something like this Barrel Organ?

Wow! that is quite a catalog! thanks for the link.
Looking at some of the related YouTube links to the one I posted above, there are several demonstration organs and street organs that could give you some good ideas. Even replacing the punch tape/ air valves with solenoids, you could still make a cool CIM powered bellows supply and your own pipes. Fun idea!

I have a feeling that we may have to use some kind of player-piano paper like that should we be unable to program the calliope for the song.

No comment as to whether this would actually work, but if you want to avoid the problem of spin-up/spin-down time you could have a constantly spinning fan in a tube with the out-flow end covered so the air doesn’t flow through the calliope. Then a small solenoid or something could open and close the cover to allow air through. Just an idea; still would be really complicated and a lot harder than a big set of speakers.

I’ve found an old magazine from 1982 with instructions on building a mini-calliope. The air in it is produced by two hair dryers sans heating elements. It would seem that this would be a fairly easy route to go.

Neil Fraser’s (bagpipe) chanter, with one motor quietly supplying air power via 3 bicycle pumps. (The website explains why 3 is ideal.) An air bag reservoir helps balance the air pressure.

Here is the obligatory music video, and here shows more of the air compressor.