Extendo Hand





Introduction: Extendo Hand

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Sometimes wish I had an extendo hand to help me reach things that are just a little too far away. For instance, picking plums off of the trees around here in Santa Clara, they are usually just about 12 inches too far away for me.

This is totally ridiculous, I know, but here it is...

here's my boyfriend Greg picking plums with it:

Step 1: Stuff You Need

a wrist brace (you can find these at Safeway made by Ace bandages)
5 spring type door stoppers
some wood and some screws
5 large washers with holes big enough to fit your fingers through
some string
some eyelet screws to guide the string through
cable ties

Step 2: Attach the Fingers

attach the door stoppers to a small chunk of wood which will act sort of like the palm of the hand.

I tried a couple of different directions for the thumb, but straight up at 90 degrees seemed to be the best idea.

Step 3: Attach the Tendons

first tie the strings to the tip of the door stops underneath the rubber end caps.

then secure the string to the "knuckle" part of the door stopper with cable ties.

attach the eyelet screws to the wooden palm and guide the strings through them.

Step 4: Attach the Hand to the Arm Bone

attach the palm to a long stick of wood to be the arm with screws.

attach the wrist guard to the wood at the other end with screws also.

Step 5: Adjust the String Length

put your hand inside the wrist guard and tighten it down with the velcro straps. You may need to add some velcro to the backside of the wood for it to grab onto.

carefully connect the large washers to the tendon strings and align them so the inside holes just reach the tips of your fingers.

Step 6: Now Go and Grab Some Stuff!

We tried this out on the trees outside and it kind of works for reaching up really high to get plums.

The fingers aren't too strong though, they keep shifting to the sides a little. And it needs some padding under the knuckles and on the finger rings if you're going to use it a lot.



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    I will post some pictures soon, I made one that didnt quite work but I have a great Idea to modify it a little bit from your design.

    Im making one righ now!

    cool, maybe share some pictures when you're done?

    I like these videos they are really fun, makes me want one too.


    Awesome!, it grabs just like a real hand :D! wraps around the item.

    Now I can go dumpster-Diving in style! At least it won't cost me $29.95! Thanx! I'd sure as hell like to try it out! Hard Tymes

    I'll spoil the mood by saying 'stick to XP'

    Neato! I've been sort of planning on doing something like this myself (probably with a slightly larger model of my own hand), but with actual joints on each of the fingers + thumb. It'll be really complicated, but I'm thinking of using a system similar to the cables on bicycle brakes for flexing.

    Yes, my first thought was to use something called "aircraft cable" which is a very strong and thin stranded metal cable. I got some from OSH but then when I went to cut it, none of my wire cutters or other tools could make a pass through it. OSH was out of cable cutters, so I just went with string which worked out well enough.

    OSH? Isn't that Occupational Saftey Hazard? (Im not being stupid, it's a serious question)