Robot arm servo power source

Other Hardware General Electronics
1

Hi,

I am planning to build a small robot arm as a home project. I will be using 3 MG996R and 3 SG90 servos. The problem that I have is that I have no idea what kind of power source to get, the arm won't be mobile so I'm looking at some kind of wall power adapter.

As this is a home project, it isn't necessary to be able to move all the servos at the same time (2 MG996R or 2 SG90's at a time is good enough). I have a spare 5V 2A adapter at hand but I don't know if that will cut it.

Any insight would be greatly appreciated :slight_smile:

2

vladimir97:
it isn't necessary to be able to move all the servos at the same time...

The problem is that the do move all the time, to get to the final position and to keep that position.
The MG996R has a stall current of 2.5A@6volt, the SG90 0.65A@6volt.
Most of the servo problems posted here turns out be be inadequate supply.
Leo..

3

Servos don't only need power when they are moving. It also takes power to hold position against a load (like holding an arm up in the air). I'd guess you could get away with about a 5V 5A supply, but 2A is unlikely to be enough.

But MG996s work a lot better on 6V and SG90s are o.k. on that too.

Steve

4

And, when you attach them in setup(), put a delay between them so they don't draw start current at the same time:

void setup()
{
   servo1.attach(9);
   delay(300);
   servo2.attach(10);