Crafty/robotics/battery-movement help needed.

I’m working with a friend to drag another friend into the wonderful world of cosplay (yeah, I know) and we’ve promised that if she is willing to dress as Rocket, one friend will make the costume, and the other (waves sheepishly) will make a battery-operated baby Grootling in a pot for her to carry around. If none of that made the slightest sense, it’s characters from the most recent Marvel movie: Guardians of the Galaxy, and yes, we’re all aware that we’re giant dorks, thanks for sharing.

So, even if she doesn’t end up doing the costume, I sort of love the idea of having a Grootling on my desk, and I want to work with electronics and batteries and wiring and shit to further my cosplay cred/background.

But I have ZERO experience there. I looked at those little solar-powered wiggle plants, but 1) solar powered won’t work, 2) they’re TEENY, 3) everyone else is making Grootlings that way, and I want to be different.

I know enough about wiring from doing house projects that I can manage the battery/wiring power-supply end of things without setting myself or the project on fire, but I have no clue how to even research what sort of electrical circuit thingies I need to attach that will make a fairly light wire-form person dance around somewhat rhythmically. I’d rather not do a computer chip, as my computer savvy is set at ‘I can sometimes fix HTML with google’s help.’

Some electronics tech person has to know what I need. Ten years ago, I would have gone to Radio Shack, but now? Haha.

Help please?

(I’m not using those horrid air blowy tubes because they’re made of satan, also too big, also too loud, but mostly because they’re satan.)

Years back, like 40 or so, they had toys on a plastic base with a small crank sticking out the bottom. The rubber figure was moulded around a bent wire that was attached to the crank. Turn the crank and the figure wiggled around. Something like that might work with a small electric motor run on batteries. Would be difficult to make the arms move though.

Another possible solution is to find one of the old dancing coke can toys from a while back and adapt that mechanism.

I’d do it with an Arduino and some servos, but it sounds like you need something a bit simpler (I’m happy to help if you’re feeling ambitious, though!).

I’d say you want to start with something like this. It’s a low-voltage motor (just hook up to a battery) with an attached gearbox and crankshaft things.

Mount the Grootling on a flexible base, and attach with thin string or wires to the cranks. Adjust it just right and the Grootling should sway back and forth. You can attach the cranks to different points so that the arms (for instance) move differently from the body. If you wanted more complex motion, you could get a second motor that runs at a different speed (different voltage or gear ratio) and control some parts of the Grootling with that instead.

I think the Arduino chip idea is a little beyond me; I think I may have understood roughly 40% of the wiki article? Yeah. I think I’ll start with basic mechanics and wiring circuits before I try programming anything.

The motor with the gears sounds like it could work. I also wonder about those puppets with ‘cable controls’ - (if you google ‘shoulder dragon’ you’ll see lots of them) does that sort of mechanism seem like it could work to control the Grootling? It’s some sort of tension cable? Maybe?

I would prefer a method where the control wires are internal, just because that makes it more exciting for people to see it and not know how it works.

They’re really useful devices and generally easier than they look, but if you want to learn you’ll probably want a simpler project to start with. Blinking LEDs are always a good start :).

That might be a bit tough, though not impossible. One possibility is to use something a bit like what I described, but instead of external control wires, run the wires up Groot’s “spine”. Pulling on one wire vs the other should bend Groot in that direction. It will require more force than with external wires, but I think the motor I linked to should still work. You’ll need to run the wires through some smooth tubes that are bundled together in a way that they can bend fairly easily and not bind. This might be tough; I’m having a hard time thinking of materials that would work. Maybe some very thin polyethylene tubing. The outside would be covered with bark, of course.

Would it matter if the tubing was a little on the big side? Our rural hardware/vet-supply/everything fixer-upper store sells various types of tubing, from latex (probably too floppy) to that clear thick-walled stuff you see in medical equipment.

It looks like the puppets I was looking at use bike-brake-cables, attached to joints or “floating” moveable areas, and use varied pressure (from a hand control) to impart movement to the joints/floaty bits. That *might *work well for the arms and head, but I don’t think it will work for the movement of the body.

So far, the gearbox is looking like the best bet for the body - I’m thinking a couple/three limited-range joints with the wires attached to the two different gears would make an interesting randomized side-to-side swaying sort of motion.

I’m certainly not going to google this from work, but I have seen… demonstrations online of vibrators that… gyrate. So to speak. I don’t know if it’s possible to set them to gyrate without buzzing, though.

Exactly what motion do you want the Grootling to make? Just how big do you want it to be?

If I had to do it using stuff I have on hand, I’d just make a Groot cover for my singing and dancing Larry The Cucumber, and clip the speaker wires so it no longer sings. I agree with the dancing coke can suggestion. That would give you rotary motion.

Hmm, I have to think some more and get back to you.

Hmm, either of those seem interesting. They’re both way fatter than they should be, but presumably they have skinnier guts? I’d love to see their innards and see how they work, but I don’t know that I want to spend $25 or so for each one just for curiousity/research.

And I had thought about vibrators, but they are essentially a motor with an off-kilter disk that spins really rapidly, and the offkilterness makes it vibrate (noise and motion) - think like a really teeny off-balance washing machine. A vibrator that gyrates seems promising, but is likely to be more expensive than the dancing coke or the dancing Larry the cucumber (seems like someone didn’t think that through quite well, actually).

All ideas are really thought-provoking so far. I guess I need to decide ahead of time how much I’m willing to lay out for research and prepwork, and just go ahead and start experimenting hands-on.

ETA - size isn’t set in stone. Somewhere between 8 and 14 inches tall, not counting the pot? I want the central stalk to gyrate, and the head to bob and turn, and the arms to wag gently from about 45 degrees vertical angle to about 135 degrees vertical angle, and maybe wag back and forth a teeny bit.

If you decide to try flexible cables, visit a hobby shop that has model airplane supplies and look at the flexible pushrods used for radio controlled aircraft. There’s a semi flexible housing with another tube running inside. They can make sweeping curves with little friction. They’ll also have clevis and other fitting to go with them.

Easy way:
Buy one
Buy a different dancing toy and re-make a Grootling.

Cheap and easy:
Design and build your own old school push puppet. Not powered by electricty; manual only.

Something that popped into my head (unsure how easy/feasible):
Levitron toy with a Grootling on top.

Build your own (it looks like it is in English but I don’t understand a lot of it):

Buy a Levitron and stick a Grootling on top (not really a dancing toy…but a FLOATING Grootling):

I see this as your best bet. If you want to go a different route-

Avoid vibrators. In my limited experience, they’re quite pricey. I’d go with a simple motor from something in the dollar store. Build a stem from either a lot of pipe cleaners, or from a thin wire coat hanger. For a cover, go with either a light cloth or a brown paper bag (obviously this would need trimming, twisting and painting). What about just making the arms of springy material rather than having a cam move them?

Point one, the point is not to buy one, it is to increase my experience and skills in electronics and mech-work in cosplaying and prop-making. If I wanted to buy one, I’m very aware that licenced merch is available for sale.

Point two, my very first post mentioned that the solar-powered flowers are too small for what I want. I’m on the fence about other possible “dancing” or movement toys.

While a “hover-groot” sounds funny, I can’t imagine that those mag-lev toys are designed to hold any sort of weight and still function.

I agree that vibrator motors are way expensive and not really tailored to what I need.

The hobby-airplane cables seem very interesting, although potentially expensive.

I have a feeling I’m going to break down and buy a “dancing coke” or “dancing Larry” to dissect and poke at the innards.

My goal would be to re-create something similar that I built myself, rather than to simply “re-clothe” the existing insides, but who knows - they may be perfect, and building a framework skeleton might be outside my skill levels right now, or some sort of hybrid design might work, based on their existing guts.