Flexy-Hand

Greetings all,

The Flexy-Hand - A proof of concept printable hand with "live hinge" flexible joints. Individually activated fingers using Filaflex filament as tendons (Alternatively use Nylon fishing wire) :

http://thingiverse-production.s3.ama...play_large.jpg
http://thingiverse-production.s3.ama...play_large.jpg

Printed in Makerbot Translucent Red and Filaflex hinges. Re-mix this idea into your own robotic or prosthetic project.

• Fingers open automatically, no return tendons or springs needed.
• "Frictionless" articulation - no rubbing parts.
• Stretchable tendons offering adaptive grip on irregular objects (only one motor required to activate all fingers).
• Fully printable solution, no vitamins required.
• Tough and rugged.
• Realistic form under a surgical glove.

http://youtu.be/K8mtqPTJ-Ys

http://www.thingiverse.com/thing:242639

Thank you for reading.
Steve Wood (AKA Gyrobot)
w: http://www.gyrobot.co.uk
f: http://www.facebook.com/gyrobotuk
tw: @gyrobotuk

That looks really well done, Steve.

That's truly awesome! Did you guys come up with this idea from scratch or is it a remix of another project?

Also, how do the tendons work if someone were to use this as a prosthetic? How would a person bend their fingers using these tendons if they were missing a hand?

I am into flexible filament printing at the moment and this was my idea for 3D printing combination of materials, to give interesting results. This could be printed with a dual extruder machine, with each material being printed with each extruder.

The idea wasn't to offer a direct prosthetic, just to sow the seed of thought into those developers out there who are more specialised in this field. Having said that the hinged figers could be a direct replacement on the Robohand project, using nylon fishing wire as the tendons instead.

I love this. This is a dream prosthetic for the right person. Did you get my PM Gyrobot?
Ed

Nice work! The range of motion is very short but could be extended with a little modification. The thumb should be able to touch the index finger at the very least. Range of motion is definitely one of the challenges when making prosthetics. Also getting the segments to move fluidly with little effort is another challenge. When I saw this I immediatly pictured a set of small servos pulling each tendon. :)

Quote:

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Originally Posted by intohim

Also, how do the tendons work if someone were to use this as a prosthetic? How would a person bend their fingers using these tendons if they were missing a hand?

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I'm also curious as to how someone missing a hand could integrate the tendons into their arm so that when they want to close one finger, it will do so. Would it need some sort of motor? I'm not familiar with how traditional prosthetics work. Is there a way to use the electrical impulses from the brain to make the tendons react?

Quote:

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Originally Posted by Jeeplvr

Nice work! The range of motion is very short but could be extended with a little modification. The thumb should be able to touch the index finger at the very least. Range of motion is definitely one of the challenges when making prosthetics. Also getting the segments to move fluidly with little effort is another challenge. When I saw this I immediatly pictured a set of small servos pulling each tendon. :)

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Trust me, the thumb and index finger do touch, tomorrow I will upload pictures of this pose.

Quote:

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Originally Posted by Jeeplvr

Nice work! The range of motion is very short but could be extended with a little modification. The thumb should be able to touch the index finger at the very least. Range of motion is definitely one of the challenges when making prosthetics. Also getting the segments to move fluidly with little effort is another challenge. When I saw this I immediatly pictured a set of small servos pulling each tendon. :)

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Here are some images showing the thumb touching the first two fingers, and close to the ring finger.

http://thingiverse-production.s3.ama...play_large.jpg

http://thingiverse-production.s3.ama...play_large.jpg

http://thingiverse-production.s3.ama...play_large.jpg

Thanks for showing these. This should clear some things up :)

BTW, we just published an article on the Flexy-Hand!

The Flexy-Hand, The Most Innovative, Useful, Realistic Looking 3D Printed Prosthetic Hand Yet http://3dprint.com/1500/the-flexy-ha...ed-prosthetic/