Animatronic Star Wars costume... can this be done?

Pam Simpson

Hi, everyone.

I've been doing simple electronics projects (lightsabers, etc) for a while now.· I recently decided to learn about microcontrollers, so I picked up a Board of Education and BASIC Stamp 2.· I was thrilled to realize that I'd finally have a use for·the Basic programming I learned in high school in the 80's!·This might be too complicated for a beginner like myself, but I have an idea for a project and I thought I'd run it past those who know more about designing electonics projects than I do,·to see if it might be possible.·

I belong to the 501st Legion and Rebel Legion, which are Star Wars costuming groups.· We regularly visit schools, hospitals, parades, and various charity and family-oriented events.· I often dress as a Twi'lek, which the kids love.· I normally have lekku (the head tentacles) that just hang down in back, but·to look more realistic·the lekku are·supposed to move.· I know how to make cable controlled animatronics, and I know that servos can be used to control those cables... so I'm wondering if it would be possible to program a set of servos to give my lekku a more lifelike look.· The biggest problems will be limiting the weight, and the confined space inside the headpiece.· There's not a lot of room in that curve to hold everything!

Here's a picture to show how the headpiece fits, and how much room is inside:

http://chucrew.com/Twilek/aaylasecura.html


Ideally I would like to have two servos inside each lekku, so that there can be both front-back and side-side motion, but I would settle for just one servo in each lekku if that's all I can manage for now.· My hope is to have a program written that would move the servos VERY SLOWLY, like the tip of·a cat's tail that is slowly waving back and forth.· I don't want a lot of motion on the back of my head giving me whiplash!· It wouldn't be necessary for the servos to be moving all of the time.· Perhaps a switch could be hidden somewhere, so that when I press it the servos would run through a minute or·two of programmed motions.· Since battery packs·tend to be heavy, I could carry a bag/purse and put the batteries in that.· I could hide the power cord on the underneath side of the purse strap to keep them out of view.· That would make it easy to change out the batteries if they run low, also.

Here are a couple videos that show the general cable-controlled concept that I'm talking about:

http://www.youtube.com/watch?v=rTh5LhYNCTw

http://www.youtube.com/watch?v=BZ4RXCumwI8


My main challenge right now is understanding how the servos should be hooked up and controlled, and how to assemble everything into a headpiece.· It's one thing to plug the servos into the Board of Education... and another thing entirely to look at an empty headpiece and wonder how in the world to make this idea work!

Thanks,

Pam :-)

allanlane5

Love the "Squid-Baby" video -- delightfully creepy. Though the puppeteer seemed to be using a LOT of muscle (compared to your typical servo) to get the motion.

allanlane5

The "Cat-Tail" video gives a nice idea of an approach that would work -- have the servo connected to a large flat disk, which has the side-strings on it. The servo can then pivot the disk, which will 'swing' or 'wag' the tentacle. This might take an inch of thickness for the servo-plus-disk, which might be too much -- but that's one approach that could work.

Franklin

I would start work on the mechanics first. Get the design down and tested (I would start with just getting the last quarter or third to move. From that you can figure out your power needs and refine your design to reduce this. Then find servos/steppers that can handle the job. After that you can look at a processor and code.

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- Stephen

allanlane5

Oh, one thing I forgot to mention -- Servo's are not "silent", at least not the ones Parallax sells. When they move, they have a more-or-less attractive robotic "whine" to them -- so sound-deadening, or finding a silent strong servo, might be one of the things you'd have to do.

The bottom line answer seems to be "Yes, this will work, with a fairly simple BS2 program driving 2 servo's." So the electronics and programming is simple and straightforward. All the OTHER issues -- rigging up the disks and strings like the "squid-baby", making it move silently, finding someplace to put the batteries could be the bigger problems.

Pam Simpson

Thanks, guys. Like any other new project, this will all be a learning experience for me. As long as I know it can be done, I can work toward getting it done! The key to the flexibility and power needs will be dependent on keeping the inner core as flexible as possible, so that it doesn't take a lot of power to bend it. I only want the last third or so of the lekku to move, so that shouldn't be too much of a problem.

I'm familiar with the squeaky whine of servos, so I planned ahead for that: I'm in the process of making a new costume for a character who has a prosthetic lekku. (In her backstory, she lost a lekku and had it replaced with a mechanical one.) It looks metallic... so the noise of something moving inside would fit!

http://starwars.wikia.com/wiki/File:RiannaSaren-LA.jpg

Pam :-)

hover1

This was in the Robotics forum a few days ago:

http://www.festo.com/cms/en-gb_gb/13254.htm

Click on Trailer 2010 if it doesn't start the video.

It looks like linear actuators would be a good fit for the project, but there doesn't look like there is enough room in the headress for them.

Jim

Pam Simpson said...
Thanks, guys. Like any other new project, this will all be a learning experience for me. As long as I know it can be done, I can work toward getting it done! The key to the flexibility and power needs will be dependent on keeping the inner core as flexible as possible, so that it doesn't take a lot of power to bend it. I only want the last third or so of the lekku to move, so that shouldn't be too much of a problem.

I'm familiar with the squeaky whine of servos, so I planned ahead for that: I'm in the process of making a new costume for a character who has a prosthetic lekku. (In her backstory, she lost a lekku and had it replaced with a mechanical one.) It looks metallic... so the noise of something moving inside would fit!

http://starwars.wikia.com/wiki/File:RiannaSaren-LA.jpg

Pam :-)

skylight

I was wondering whether the memory/muscle wire that was shown in another post(can't remember which) would work? send a current through it and it contracts.

Just found out its called nitinol
here's a video of it in use
looks strong enough to do what you want

www.youtube.com/watch?v=rQbzgW-hbDg

Post Edited (skylight) : 6/21/2010 7:48:47 PM GMT

hover1

I have tried muscle wire, and it only works on the lightest of material. I did some butterfly wings that were so light, I had no way to measure the weight.

Pneumatics would be the quiet way to go, but where would you hide the compressor. I always run into this when I have done animitronics with servos and the customer has a problem with the servo whine. But then they don't want to install all the stuff associated with pneumatics.

Jim

skylight said...
I was wondering whether the memory/muscle wire that was shown in another post(can't remember which) would work? send a current through it and it contracts.

WBA Consulting

The servos could be muffled inside sound deadening material. Dynamat could be used to surround the servo and just leave the horn exposed. Or, the servos could be packed in an insulated box where just the cables protrude. I honestly don't think servo whine will be a major issue, especially if you limit the movements to slower rhythmatic type movements as opposed to jerky, "whipping around" type movements.

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Andrew Williams
WBA Consulting
PowerTwig Dual Output Power Supply Module
My Prop projects: Reverse Geo-Cache Box, Custom Metronome, Micro Plunge Logger

W9GFO

Out of the various servos that I own the JR brand is the quietest. Like WBA said, if you keep the movements slow, it shouldn't be noticeable.

I would not use a digital servo for this because they tend to be noisier when not under a load.

Rich H

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The Simple Servo Tester, a kit from Gadget Gangster.

FireHopper

I use servos in my animatronic wings, and I am currently working the kinks out of the controll code thanks to beau on the robotics forum. You can find pictures of my costume this website [noparse]:)[/noparse]

http://www.parallax.com/ProductInfo/tabid/652/Default.aspx there [noparse]:)[/noparse] its been updated with new batterys and new controller so the photos are not up to date anymore..

I am using 2 cell Li-fe po4 battery packs, used to use 8 aa and 8 D cells.. making it quite heavy, I now use 3 2 cell packs, the weight is less than it used to be, and are easy to charge with special chargers. they could be charged in 15 mins or less. I tend to charge over night to let them last longer [noparse]:)[/noparse]

Robomaster

Hi Pam and everyone,
I like what you are planning to do and would like to offer my service to get the mechanics working for you. I am an animatronics expert. Please check my web site at this address www.magicandtechnology.com ·. I worked on the movie “Operation Dumbo Drop” where we worked a life-size animatronics elephant with a really cool trunk mechanism. ·I can make a light weight mechanism that will fit in the headdress area.
Tim Lewis
·

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Tim J Lewis

Pam Simpson

Hi, everyone.

I'm making good progress on the costume, and I hope to start working on the mechanical aspects of it within the next couple weeks. I've been experimenting with different shores of silicone rubber to find which combination allows for the best movement, but also supports the weight of the lekku.

Tim, thank you for the offer, but the whole point of this project is to learn about something new. Through costuming I've learned about everything from sewing to casting in fiberglass. Now I'm taking another step, and learning how to build and program the servo mechanism is more important to me than getting a finished product in the mail!

Pam

hover1

Pam,

I like you attitude! Pleas keep us updated.

Jim

Pam Simpson said...
Hi, everyone.

I'm making good progress on the costume, and I hope to start working on the mechanical aspects of it within the next couple weeks. I've been experimenting with different shores of silicone rubber to find which combination allows for the best movement, but also supports the weight of the lekku.

Tim, thank you for the offer, but the whole point of this project is to learn about something new. Through costuming I've learned about everything from sewing to casting in fiberglass. Now I'm taking another step, and learning how to build and program the servo mechanism is more important to me than getting a finished product in the mail!

Pam