problem with supply on a hexapod robot

Greetings for all

I dont know how to supply my hexapod eight servo robot with an arduino uno. Actually it have 8 servos. And wen I connect the 4AA battery does not work as should be. All servos become unstable and not work. What I need for supply them well?

I appreciate your help

When you say they do not work, do you mean not at all? What do you mean by unstable?

First things first: have you got the ground of the servo battery pack connected to the Arduino ground?

If that's not the problem, then I'm guessing that 4xAAs can't provide enough current to all of those servos. So maybe get at least another battery pack and supply 4 servos with one and 4 with the other? Or get 4 and supply 2/2/2/2.

8 servos may be peaking at 5A or even 10A - AA's are probably not upto it (what exact batteries are you
using though?)

What's the voltage rating of the servos (max and min)?

JimboZA:
When you say they do not work, do you mean not at all? What do you mean by unstable?

First things first: have you got the ground of the servo battery pack connected to the Arduino ground?

If that's not the problem, then I'm guessing that 4xAAs can't provide enough current to all of those servos. So maybe get at least another battery pack and supply 4 servos with one and 4 with the other? Or get 4 and supply 2/2/2/2.

When I pull the switch of the power some times do erratic movements or some times not work at all. I have the ground of the servo battery pack connected to the arduino through a medium protoboard. That is not the problem. I'm sure its a supply problem. I will try what u say, thanks. If u have another recommendation please let me know.

MarkT:
8 servos may be peaking at 5A or even 10A - AA's are probably not upto it (what exact batteries are you
using though?)

What's the voltage rating of the servos (max and min)?

I'm using 4 AA alkaline battery of 15A and 1.5v each.

I'm using standard servos. The voltage rating is 4v~6v

4 AA alkaline battery of 15A

Wow.....

You need to use a shield with the Arduino Uno for that many servo. Get one that has a power terminal on it and supply the power directly to the shield. You will still have to supply power to the Uno also. Change your battery to a NiCD, Nimh or Lipo for the amperage you need, dry cell batteries will not power that many servos. I made a power connector for my bots which use many servo that powers both the shield and the Arduino.

I'm using 4 AA alkaline battery of 15A and 1.5v each. I'm using standard servos. The voltage rating is 4v~6v

If the batterys will operate the servos with only one or two servos connected, then you need a better battery supply. The battery holders like from radioshack have small wires and may not work well with more than one or two servos. You really need to swap to rechargable batterys instead of alkaline ones unless you have a lot of $$$.

How does a hexapod work with 8 servos ?