Hi mikimasa67,
Yes, you can add more servos to projects. It is usually as easy as wiring up another servo and changing the code.
Instantiate another servo object, with the new pin number in the attach method.
Then put in code to tell the servo to move the way you want it to move.
Note that MANY new arduino users attempt to power the servos off of the arduino 5v pin. This is almost always a problem as soon as you add servos or try to make the servos actually move something.
Google separate power supply for the servo.
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mikimasa67, your code is hard to read because it is not in code tags.
Can you edit your posts to use them?
Have you tried your code? You do not need the head attached to test the code - just 2 servos. And a separate power supply.
@mikimasa67
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Bob.