Science Buddies: "Ask an Expert"

I have to make a hand prosthesis for a science project using things around the house. The hand has to be able to pick up an empty coke can. I have tried finding information on the internet, but have had no luck. Does anyone out there have any suggestions that might help me out? I'm running out of time and have no ideas at the moment. Please help!

Hi samakar1516.

I need to know how simple or complex your hand prosthesis needs to be?

This is a suggestion for about the simplest device that I can think of:

1. Use a plastic soft drink bottle, like a Sprite 16.9 ounce bottle,
500 ml, 1.06 pt, on the label,
or any soft drink bottle made like this description.
=======
2. Make sure the bottle has the shape similar to an hour glass,
smaller in about the middle of the bottle
with curved "bumps" that look kind of like "fingers" at bottom.
=======
3. IMPORTANT SAFETY PRECAUTION for this STEP:
Have an adult cut the bottom of the bottle off
using a kitchen knife and scissors.
=======
5. IMPORTANT SAFETY PRECAUTION for this STEP:
Cut straight lines from the bottom of the bottle,
in between the the curved "fingers," with scissors,
to near the neck of the bottle just before the cone shape starts.
Be sure and leave the curved part of the bottle
with the curved bumps, "fingers," at the bottom.
Cut about one fourth (1/4th) of the bottle side on top side,
then do same thing on the bottom side
looking down on the bottle on it's side.
=======
6. The bottle should look similar to the diagram below
after cutting is finished.
IMPORTANT:
Cut out a curve shape near the middle of the sides,
with scissors, to hold the can you will be picking up.
=======
7. You can figure out how you can attach the neck of the bottle
to something to attach to your arm,
like a small stick, rule, yard stick, and tape or a big rubber band
to hold it on your arm.


Soft drink bottle hand prosthesis diagram:

.............=====
.............=====
............(...I--I...)
...........(....I--I....)
..........(.....I--I.....)
.........(..+..I--I..+..)....++------ Cut a curve out on this part toward neck.
.........(..+..I--I..+..)....++------
...........(....I--I....).......++------ This will keep the soft drink can
.............(..I--I..).........++------ from falling out when you pick it up.
...........(....I--I....)
..........(.....I--I.....)
..........(.....I--I.....)
...........(())I--I(())
...........(())I--I(())
................I--I
................I--I............... Cut one fourth (1/4th) of the bottle out
.................................... on top and bottom sides.


Please let me know if this helpful, too simple, too complicated, don't understand, or any questions you have.

I hope this helps.

Good Luck!

Thank you very mych for your help, it sounds pretty easy, but the diagram didn't show up. Could you possibly send it again, a different format maybe? Also, how do you get it to grasp the empty coke can? Thank you very mych for your help and I look forward to hearing from you again really soon with the answers to my questions above.

Hi samakar1516.

Let me know if the diagram is useable now?

Thanks.

I'm sorry to bother you again...I did get the diagram, thank you very much. But I do have a question.....how do I get the "fingers" to pick up the can? I basically have a picture in my mind of how the bottle is going to look, but I'm not seeing how it is going to grasp the can. Thanks again for all your help.

Hi samakar1516.

I apologize for leaving out the most important part.

I will try and explain how this hand prosthesis device will work
to pick up the empty soft drink can.

To see how to go about making the hand prosthesis device:

1. Place a plastic soft drink bottle on it's side on a table.

2. Hold a soft drink aluminum can on the top of the side of the bottle.

3. Hold the can in the middle of the bottle's side.

4. What we want to do is to make a "hole" in the bottle
just a little smaller than the can diameter
so the stiff plastic sides will grip the can.

5. You need to do this by following the steps described
in my first Post, using the diagram as a guide.

6. You need to cut the bottom of the plastic bottle off first,
just far enough back from the bottom so the "fingers"
will still have some "bend" or curve like on the ends.

7. By cutting out a "slot" on top and bottom of the bottle sides,
then making the middle part of the bottle look like a "hole"
that will grip and hold the can when you either,
a. Push the bottle "hole" over the can from the top of the can
or
b. Push the bottle "fingers" against the side of can until the can is in the "hole."
You might need to have the back of the can sitting against something to keep it from moving or use one of your other hands to hold it while you pick it up if you are allowed to do this in your project.

8. You should be able to pick up the empty aluminum can with the plastic
bottle, "hand prosthesis," either way described in step 7 above.


The main idea behind this device is to use the stiff, flexible, plastic
of the bottle to grip the aluminum can while picking up the can.
The bottle kind of looks like some hand features, like the "fingers."

You might want to ask your Teacher about this idea first.
This may not be acceptable for your project.

It was just the fastest and easiest thing I could think of
to try and help you.

Please let me know how you are doing and how I can help.

Good Luck!

Hi samakar1516.

Please leave us a Post to let us know if you were
able to use the information provided on this Forum
to complete your project.

Did you get your hand prosthesis device made or not?

Thanks.