# Robotic arm project help

1. Jun 19, 2013

### ttouch

Hello,

I'm a complete noob on the robotics.
I got an idea, to build a really cheap robotic arm (~$60). I thought about using 4 servos (rotate the arm, move up/down the first part, move up/down the second part and open/close the grippers). As the bone material I found that 1m aluminium tube (2mm thick wall and 5cm diameter) costs about 5$. I don't want the arm to be very big, so the first part could be 40cm and the second 30cm.
Also I need it to be able to lift 500g (is that a bit too much?)

I have an Arduino which is ok for controlling some servos.

I know I don't give enough data, but that is just a thought. I have no idea how to design it in the computer (zero knowledge of AutoCAD)

Problems:
Is this even possible? (I don't see any problems, but as said, I'm a noob)
What servos do I need? How much torque? (aluminium is very lightweight...)

Thank you

2. Jul 4, 2013

### HHOboy

Well I think it is possible but maybe not a 500g load unless you are using hydraulics. I was actually on a science Olympiad team in highschool and was given the task to build a robot arm from scratch. I used arduino and as far as the servos go I used Futaba S3003's (Not very powerful). For the body I used a kit I found online it was made of laser cut wood. To control it I used 2 joysticks from a ps2 controller.

I actually happened to have made a video of the arm on youtube a wile back if you want to watch it the link is here-

As far as your robot I think it would be possible to build it out of that tube but I was wondering what kind of resources you have available like do you happen to have access to a laser cutter, how do you plan on building the skeleton?

As far as servos go you are going to want to use large ones. Also you will need an external battery for the servos because the arduino can't handle more than about 2 small ones and I think but make sure you remember to connect the ground from the arduino and the ground on the battery haha that always gets me lol.
If you want to you can just buy the skeleton already created with all the servos that work with it.
Here is a ebay link http://www.ebay.com/itm/New-6-DOF-M...011?pt=LH_DefaultDomain_0&hash=item3cd13fef9b