cool!
Cool arm! Now I have something to do with all those robot part boxes 
I say run some string up
I say run some string up through the arm to various points and make it move 
Polymorph
If don’t want to hotglue your servo to the cardboard, try out polymorph. It’s really easy to work with and reusable.
** You said "I chose to make**
You said "I chose to make it out of cardboard instead of making a CAD model cause I thought it would be FUN! :p"
That sentence alone is worth my top rating for this project.
Daring to take a differnt approach and going for “fun” over “practical” is what will spawn new ideas.
/ vzz-clck-“Maneuver”
Yeah video makes a project
Good one.
I noticed you removed the push pins from the pivots. They are replaced by the servo on one side of the arm. Any plans for the other side, that you would like to share?
Also, you do realize that you posted your zipcode and phone number on the Great Wide Internets, right?
Rik
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Yeah…
Yeah I know I posted my info right there for the internet to see…however I was smart enough to sharpie out my street address. I’ll get that fix…
As for the pivot, I’m not using them for this cardboard version, however, when I construct it out of HDPE I have a few choices.
I could just use simple pins and call it a day.
I could use berrings and have a real rugged, solid, friction “free”, pivoit.
I could use another servo. This option is more appealing to me, however, more expensive.
I think I’m going to use berrings…
Aruduino power…
They’re getting there power from the Arduino. I don’t know the max current draw on the 5v power pin of the arduino…but it hasn’t been enough to reset. Those servos apparently draw about 150mA while operating unloaded so god only knows what’s going on…and so would my multimeter if I took some time to check it.
The servos have a rating of 49oz/in, but I guess cardboard is just to heavy.
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The curse of the arm…
When I was designing Walter’s head, I thought about an arm instead of the x,y,z I have now… Of course I was looking at the cool servo driven arms available in the 300 to 400 dollar range. It was then that I really found out about servo torque. And here is what I found… Servos are weak. A standard servo is rated between 40 and 60 oz/in which means at 1" from the pivot, it can lift, say, 50oz. Now lets stick a 4" arm onto that leading to the next joint. Now we have 50/4 = about 12 or so. Add another servo at that joint and we loose about an oz and we are about down to 10 oz it can lift. Add another 4" section and a servo on top of that and you are soon to the place where your arm can’t even lift itself. On the arms I looked at they were using (2) high torque servos at the bottom and elbow minium. I did some looking and it seems better to use one 1/4 scale servo for the base, hi-torque for first and second joints and standards and mini’s from there.
Hope this helps, all I am saying is when I did the math, it got expencive quick.
