Introduction: How to Build a Galileo Hand. Author: +Ali Lemus
VERY IMPORTANT!!!
Author : +Ali Lemus
This is a english version of a Spanish version found here:
https://www.instructables.com/id/Como-construir-la-...
any mistakes in the translation, please collaborate to make this document better.
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GalileoHand is a project of the ideas to make low-cost prosthesis, made with 3D printers and files available for free download. The prosthetic hand GalileoHand was designed to conform to conventional mechanical prostheses, replacing the terminal device is usually a hook or tweezers and retaining the traditional drive which can open and close the fingers. One improvement to this design is that by means of a locking mechanism of the thumb enables rotation thereof to place it in three different types of grips, these being bidigital Pinza, three digit Tweezer , lateral pinch.
This instructable shows the steps to print and assemble the Galileo hand.
Step 1: Step 1.- Printing Pieces and Materials. Author: +Ali Lemus
.STL files can be downloaded here:
http://www.thingiverse.com/thing:655432 instructions attached. 20 pieces to print
Materials:
1 ballpoint spring.
1 rivet.
Elastic cord.
Nylon Non elastic cord 1 mm.
SuperGlue.
(OPCIONAL)
Lighter
Bike brake iron wire
Piece to hold the iron wire
PLA o ABS filament for axes of rotation of fingers
Step 2: Step 2: Joining the Fingers. Author: +Ali Lemus
You must remove the debris left by the printing process. With all the pieces together you must join them so that it can rotate the upper part and the lower part, making a bond between them.
Axes of rotation.
For this we need a rotation axe for the upper and lower part. You have two options, like screws with 3mm diameter maximum. So the essential for this axis is that must be supported by the outter parts of the piece like is shown in figure 4.
Another option is to use a PLA or ABS filament to be the rotation axis. For this you must to cut a small piece of filament bigger than the width of the finger part, then get the filament into the upper and lower parts to get them bond [ image 3 ], then you must heat a flat surface to the point of melt the filament, and the filament ends also must be melted to not to get out of his rotation axis. [image3]
This must be repeated with the five printed fingers.
Elastic cords
After placing the rotating axe on the top of the fingers we must introduce the elastic cords, these are placed to keep the fingers in a open position and capable of closing action. This is done before join them to the Palm.
Joining the fingers with the palm
Uniting the fingers into the palm of the hand is the same procedure described above, to avoid problems with the assembly we recommend starting with the Middle Finger.
once all the fingers are subject must adjust the elastic conducting a simple knot, finally have to get them trough to the bottom of the finger as shown in [Figure 5]
All the steps are shown in the next video
Step 3: Step 3 .- Joining the Thumb. Author: +Ali Lemus
the following steps, some already described in the previous Steps.
Thumb_Prox.STL and Thumb_top.STL parts must be connected through filament
Get the Elastic Lace and Nylon Cord through
Perform a knot the elastic cord so keep it in position
Fix the Thumb with Part ThumbPalmUnion.STL
Assembling the locking mechanism [1]
Introducing the nylon cord in the palm set the axis of rotation of the thumb piece Screw.STL
[1] Locking Mechanism: need a little spring (pen) and a rivet diameter 3 mm long and 3 cm, for the locking mechanism shown in the images and to slide piece rivet Slider.STL and the thumb position change, this is inserted by pushing, as shown in the video GalileoHand - Thumb assembly.
Step 4: Step 4: Adjustment Mechanism to Close the Fingers. Author: +Ali Lemus
To close the fingers is only necessary to pull the strings of nylon, elastic yarns being responsible for return to the natural position of the hand that is normally open. With cable bike and FineClose.STL [image 1] piece can pull the 5 fingers at the same time to fully close the hand.
So that the fingers close in sync threads are adjusted by simply rotating the holder.STL [image 2] which is a piece by each finger. This process is described in the video GalileoHand - Adjustment Mechanism to close the fingers.