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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    55 Discussions

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    TBolt

    9 years ago on Introduction

    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.

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    CarliPierce

    10 years ago on Introduction

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

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    pls

    10 years ago on Introduction

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

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    HardTymes

    10 years ago on Introduction

    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

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    foobear

    10 years ago on Introduction

    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.

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    minerugfoobear

    Reply 10 years ago on Introduction

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

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    Nimphiousminerug

    Reply 10 years ago on Introduction

    I think you're referring to OHS, Occupational Health and Safety, I don't think the hazards have an acronym, although yours is reasonable enough.

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    minerugNimphious

    Reply 10 years ago on Introduction

    The reason I said OSH is because that's what the helth and saftey thingy-ma-bob of the government is called where I'm from (I could be confused though)

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    Nimphious

    10 years ago on Introduction

    In your next version or possibly as a revision to this version, if you plan to do either, you could add a simple pulley to the base to make the grip stronger with less effort required by the user. Since it's such a long base many pulleys could be used, although after two it might be a little ridiculous since you'd need your other arm to pull the strings far enough to fully contract the fingers. Your design is great, and the only thing I would do differently following this instructable, would be adding a string for the thumb, and some more wood at the base to allow your thumb to control it separately from the hands, allowing you to do things like shake hands and operate buttons.

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    PKM

    10 years ago on Introduction

    The twangy doorstops! I haven't seen those in ages...

    This is a really cool idea, if you wanted some next-level freakyness you could put a glove on the hand- it might make fruit-picking better (less bruising) and would look distinctly weird. Then sew extensions onto your sleeves and frighten small children with it :D

    hehehehe

    5 replies
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    foobearPKM

    Reply 10 years ago on Introduction

    I was trying to think of some sort of rubbery thing to put on the fingers to give them more gripping power. Like maybe those rubber fingers that they have at the office supply store that people used to use who handle a lot of paper.

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    PKMfoobear

    Reply 10 years ago on Introduction

    Rubber thimble? I would have thought the rubber doorstop things would have decent grip, but I suppose you could replace them with carved bits of eraser? The silver side of duct tape has fairly good grip...

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    orangesrhymePKM

    Reply 10 years ago on Introduction

    I have the twangy doorstops in pretty much every room in my house. I used to kick them, but people got really mad at me. Probably cause it was at night... okay, in the morning. One in the morning, that is.