View Full Version : Animatronic Tail
11-05-2003, 01:23 AM
I made a halfway decent Nightcrawler costume for halloween and wish to revamp it for Comicon, and whatever anime conventions i end up going to. Actually by re-vamp i basically mean start over! My biggest project is the tail, i don't want to make another cloth/clothshanger wire/cotton tail. I'm going to make an animatronic prehensile tail based on the spider monkey tail (assuming i can find a good anatomical diagram, if u by chance see one let me know, thanks ). Anyways I'm going to use something like PVC piping for the "bones" and ball bearings (or something like that) for the "joints". then using 4 eyelets on each pvc piece I will thread some sort of thread/wire/fishing line all the way through like a giant rubber band and attach them to motors in the base piece that will be able to pull the wire both directions. and it will do this for both horizontal, as well as vertical. Then i plan to rig a simple "controler" up to it all so i can control the motion of the tail.
I was thinking that if i set up this tail about 8 inches short of my goal, and then build a smaller version (which shorter bone's) that works seperately from the rest and then attach it to the first (with the same ball joint) that i can make it able to "grab" and "hold" small lightweight objects. Though this is a secondary "wish" goal.
The harness I give 100% credit to Kusanivy, her help was crucial in all of this, in fact seeing her tail design was the inspiration for this. for those who are curious it's felxible moulding and straps (like belts) that wrap around the waist and each leg which gives it a natural wagging motion and an extremely strong/stable anchor.
Anyways i'm hoping somebody can help me out, tell me what will work what won't and give advice on how to make it all work. I really appreciate everybodies help thanks!
I made a set of working wings using PVC style piping and they
where to put it mildly a disaster.
There is too much flex in one direction and by the time the joints where added the whole framework was getting heavy.
Now I grant you that a tail is a bit less material then large wings. However, the pipe may not offer the kind of flexibility that you might be looking for.
Here is a suggestion based off something that I have in mind for another project. A metal braid line covered in latex. The metal provides places that you can attack small pulleys and is hollow and flexible enough to allow decent support/pull lines. Micromotors then pulling in various sequence would allow the tail to swish a bit.
06-27-2006, 06:08 PM
animatronics seem to be some of the hardest information to obtain. I have been snobbed on numerous ocassions when I ask about how to make a working tail/ears...so If you know anything or find anything out...can you kindly pass the info on?
06-27-2006, 07:58 PM
Here's an essay for you LOL
PVC piping with ball bearings do sound REALLY heavy. You may want to go REALLY lightweight, which will make the whole thing easier to move around too, seeing as how the base of the tail will be rather immoblie due to having to support the whole weight. You may want to try something like thick paper mache over something like a paper tube, or "heavy duty" foam. Make sure it can support the ball bearings or whatever you use though. Gotta find a balance. If using something soft, skip the joints and cut channels for the moving gear.
I imagine your harness will look more or less like a jock strap, right? lol If possible, make straps or use suspenders (under the costume) so it doesn't slide down or put alot of strain on your hips.
Also, maybe what might work better than ball bearing style joints would be something like the moving parts in toy trucks, the kind that move like a knee. Just pad the tail to make it look more curved rather than joint-y. You can model it after the said toy trucks if you know enough about wiring and electrical engineering lol (look for a highschool level physics book). Connect them to move all at the same time, and fashion an extra switch to be separate wiring for the grip part. You'll have to manuver two switches, the best place to go for the controller would be a Radio Shack type place.
With each "joint" you add, try it on, to make sure its not getting too heavy. Wear it around for an hour, it may not feel like a pain right away. And if you want to, make sure you can still pose while wearing the whole thing lol
Hope this helped :D:geek:
06-27-2006, 08:01 PM
06-27-2006, 08:28 PM
Making a tail that moves in one plane wouldn't be that hard, but to make a tail that moves in multiple planes, that really compounds the complexity. To make it move in one plane, you'd have to have joints running down one axis. For each plane of movement you add, you have to add another axis of articulation. Within a tail as thin as Nightcrawler's, I doubt there's enough room inside to put that amount of intricate hardware. Plus you have to have enough clearance inside the tail so that the ligaments don't snag or bind. Thank goodness his tail doesn't taper to a point, otherwise that'd make this build nearly impossible.
Actually, instead of putting two axes of hinges into the tail to get two planes of movement, you could put one line of hinges that alternates between the two planes. This reduces the "agility" (curling radius) of the tail, but it'd be a helluva lot easier than making two fully articulated axes. You'll probably have to extend a spar up your backbone and have a belt or other harness holding it against your upper body to counter the moment of the tail, too.
Personally, I'd say forget about making the tail agile enough to hold anything. And I'd advise against putting any motors or any item of weight anywhere on the tail besides the base. That moment builds up and becomes troublesome very quickly. And since you'll have to make the tail lightweight to avoid a problematic moment, that means the tail will be fragile, meaning that one yank from a fanboy would be enough to break it. You have to consider that risk too.
P.S. When I say "hinges," I don't mean actual hinges. They can be simple pin connections, swivel connections, etc.
P.P.S. I'm working on a costume (http://images.cosplay.com/gallery.php?cat=36520&member=29388) that involves a mechanical neck (http://www.youtube.com/watch?v=dfrvjKnqQJ8). Bigger than a tail, yes, but the mechanisms are all the same. It took me two months to get it to this point and you can tell it still needs work. I'm not saying puppetry is impossible, I'm just saying it ain't easy.
06-27-2006, 11:23 PM
WolfTronix (http://www.wolftronix.com/tail/index.html) has made several working tails.
The linked site has pictures and a video.