Servos won't move

Hello,

So I've actually got three different types of servos that I've tried to use with my arduino servo driving software. Inintially I was using a phone charger as a 5V power supply but did some reading and figured that perhaps it was my power supply. Just to be clear I'm only trying to power a single servo at one time. So I moved on to bench power supply and supplied 6V with a current limit of 2A. All of the servos I've tried seem to rotates until they hit the physically stop that is build into them and then continue trying to rotate. Since the stop is there the rotation is halted and all they do is vibrate and twitch a little bit. Below is the code I'm using.

#include <Servo.h>

Servo xyServo;

int pos = 0;
void setup() {
  // put your setup code here, to run once:
    Serial.begin(9600);
    xyServo.attach(9);
}

void loop() {
  // put your main code here, to run repeatedly:
    xyServo.writeMicroseconds(1500);
    delay(1000);

    xyServo.writeMicroseconds(1000);
    delay(1000);

    xyServo.writeMicroseconds(2000);
    delay(1000);
}

I've attached a picture of my set up.
I appreciate any input :).

I've attached a picture of my set up.

Nope.

Did you connect the grounds?

Sorry initially the photo was too large. Then when I tried to edit the post it said I had to wait 5 minutes before posting again. I have now attached the picture of my set up and yes I have connected the negative terminal of the power supply to the ground pin.

As AWOL said, connect the GND on the Arduino to the GND on the servo power supply.

The photo does not show a proper ground connection.

Well thank you very much. I now feel very silly although I'm happy my servos are working.