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Functional Back Brace for Costume

  1. Sep 24, 2015 #1
    Hi, hopefully this is in the right place. I have big plans for making a Velociraptor costume and I've got a handle on how I'm putting most of it together, but there is one issue and it's a big one; comfort. I know that I'm going to be uncomfortable in the costume regardless of what I do and I'm at peace with that, but I need a method to take the stress off my back and possibly lengthen the time I can wear the costume from a few minutes to a few hours at a time.

    Essentially, the costume will require me to be doubled over forward, Here's a picture to show you what I mean:

    This position will put a lot of stress on my back so I'm looking for a way to ease it. I don't know whether a back brace would work? I know digitigrade stilts use bungee cord to alleviate pressure and act as a tendon when wearing them, so I was wondering if I could do something similar for my back?

    I also want to direct the weight of the costume to my hips since any weight on my shoulders is not going to go well for me in that position. Perhaps a backpack frame with kidney padding like so:

    As you can probably tell, I don't know much about engineering but as a cosplayer, I love to dabble in new things, from painting, special effects and construction, so any help is greatly appreciated. Tell me how to make something and I'll make it. A diagram would probably go a longer way but any input whatsoever would be great.

  2. jcsd
  3. Sep 24, 2015 #2


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    Welcome to the PF.

    One theme may be to use weight in the tail to help pull your body up -- basically balancing the torques about your hips. This will make the costume heavier overall, but with balanced weight forward and behind your hips, it should ease discomfort in your back.

    I've found that when commuting on my sportbike (which has a very forward position for my upper body), that the weight of my courier bag behind me low on my hips helps to lift up my shoulders because of the backward torque it supplies. That makes the forward position much more comfortable for me. Riding without my courier bag is definitely harder on my back, in my experience.

    I'd also suggest that you consult a professional for good advice on this. I had a friend who was an ex-paramedic and was working as a physical therapist and ergonomics consultant -- she used to be hired to help fix employee work areas to alleviate repetitive motion issues and other physical problems. If you can find such a specialist near you, they can probably help you optimize the structure inside the costume to give you the most comfortable experience possible. :smile:
  4. Sep 24, 2015 #3
    Great costume idea, very ambitious! Keep us updated and I want to see pics when it's done! :)
  5. Sep 24, 2015 #4
    Thanks for the welcome. I was planning on adding some kind of weight in the back if not just to stop me from toppling forward from the front-heavy head.
  6. Sep 24, 2015 #5


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    Webbing harness with multiple measured to place foam standoffs .
  7. Sep 24, 2015 #6


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    So seeing that you are planning some structural braces from your hips to your feet, I'd recommend putting together on overall exoskeleton that connects the leg braces to your hip, with a pivoting structure that goes up your torso to support it, and goes back to the tail counterweights. That takes the weight of the counterweight and exoskeleton off of your legs, while making your upper body "weightless" because of the balancing counterweight in your tail.

    Should be a fun project! :smile:
  8. Sep 25, 2015 #7
    So what you're recommending is something like this? :smile:


    This is the plan I had for the body. I'm going to take the templates for this pepakura model:

    And enlarge the torso/body to a size I can fit inside. The creator has done this herself for the full suit:

    Using that as a base on corrugated cardboard, strengthening the seams with fiberglass and adding upholstery foam to each face which I can then carve and curve into a dino-shape should give me a lightweight body that's still sturdy. Others have suggested making an actual skeleton and ribcage out of aluminium wrapped in foam, but I think the aluminium will be heavier.

    For the legs, I was going to have my own legs visible and attached to the dino legs, meaning I could go a bit heavier, so hinged pieces of MDF that bolt onto the side of the body at the hips should do, although just in posting, I've realised the limitations of the hinged joint compared to a proper hip swivel joint:

    But after having a look at some digitigrade stilts, I'm considering going that route instead. I was originally put off by them because I thought it would be too difficult to wear them AND be put in that forward position but after some research, the stilts are apparently easy to wear with some practice and don't change how you balance. That would mean I'd have legs concealed in the suit. Still haven't made my mind up; not sure which route is easier.

    So I get the see-saw mechanic and how I'd apply it to the costume, although how would I go about the leg braces to take the weight in relation to those two options? I kinda see how the leg brace would work in the first option where my own legs are visible; the chunks of MDF (reinforced with aluminium bars) would be a direct line to the ground, so the weight would be taken by the dino-legs but if I used my own legs, with digi-stilts, is there still a way to brace them?

    Thanks for the help, I'm slowly starting to see that this is doable, which is really encouraging. :smile:
  9. Sep 29, 2015 #8

    Do medical leg braces support your weight or are they more for correcting form and limiting movement? Still at odds with how I can take the weight of the suit off my legs. Not sure what I'll use on my legs or how to connect it to the balancing rig at my hip.
  10. Sep 29, 2015 #9


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    I don't think medical leg braces transfer upper body weight past the legs to the shoes, but I could be wrong.

    While Googling, I found this interesting resource:

    Even though their goal is a self-powered exoskeleton, it looks like most of what they have now is powered (which may still work for you). I didn't follow all the various project links at that website yet, though. :smile:
  11. Sep 29, 2015 #10


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    Are you physically anywhere near Berkeley in Northern California? If so, it looks like you should try to link up with their lab -- they may be interested in helping you with your project... :smile:
  12. Sep 29, 2015 #11


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    It appears the pepakura model, life size version, has the user upright and not hunched over, and being balanced, the weight of the thing is straight down from shoulders to the feet. The discomfort would be trying to move the paper model around, and if light would not be that difficult. And of course seeing where one is going.

    Being hunched, it is more difficult to see around you.
    I expect you will have some neck stress from trying to keep the head up, and lower back stress from the body in that position. Shoulders might begin to ache from the arms being pulled up ( as in the first picture of the man in the suit ).

    You could try putting a backpack on, hunching over and testing the discomfort and seeing how long you can last with different weights in the backpack. With the tests, by being not in the suit, you can forfeit the attempt and easily straighten up. With a suit that makes that impossible - with tired muscles you may just embarassingly topple forward. Having a means to sit or stand and rest at intervals, in the suit, should be one of your design criteria.

    Having the suit as light as possible, so as to minimize strain is one way to go.
    Having a heavier suit with some self-suit support of its own is another way to go.

    A built in pogo to sit down on could prolong the length of time to wear the suit, especially if it is difficult to get in and out of.

    Nice idea by the way.
  13. Sep 30, 2015 #12
    I'm from the UK so Berkeley would be a bit of a challenge. An exosuit might be pushing the bank a bit too, but it was one of the only things I found that might help when searching google.

    I'll scale the pepakura "mini" model up to the first picture which will require me hunched. I think for a lot of pictures, the wearer was leaned at a 45 degree angle rather than standing straight or completely hunched so it might be a bit oversized. I think a 60-70 degree angle would be the most accurate to do. The stick sounds like a good idea. As awkward as it sounds, but a telescopic pole that comes out of the groin area between my legs underneath all the weight pivoting at my hips. Can't imagine what that would look like though. Or what my 'handler' would have to do to get it out. :))

    If i balance it right though, it won't be a case of me hunching over and putting stress on my back but rather lying down, putting my all my body weight on the front side of the pivot with the weights at the back matching my forward mass. It might be difficult bending down though; may make it everso slightly front-heavy. Also, I could lower my arms. I won't be operating the dino-arms; they'll justbe dead limbs. Instead I was going to hold a controller for the raptor noises, linked to an amplifier in the mouth, so I could place them anywhere. The neck is an issue though; planning on attaching a bike helmet or something to the neck of the dinosaur, and by moving my head, I'd move the dino's head.
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