I am thinking of powering a servo with an Arduino Uno. It came in a starter kit. It is a "Tower Pro micro servo 9g sg90"Would it draw too much current, or do I not have to worry about that?
You need a different power source.
I was given the specs for that micro servo motor. It draws up to about 300 mA.
USB2 is 500 mA max
USB3 is 900 mA max.
Could you suggest some good relays that draw 20 ma at 5V max with nothing to limit current and have a very low resistance on the load side?
Could you suggest some good relays that draw 20 ma at 5V max with nothing to limit current and have a very low resistance on the load side?
Why, this has nothing to do with your original question.
You just need to connect your servo to a separate power source, connect the ground of this to the ground of the Arduino and connect the Arduino's output pin directly to the servo.
Could I just connect GND to -, a PWM pin to S, and power + and power - to + and -?
No. You need a 5-6V power supply for the servo, capable of delivering at least 1 Ampere. A 4xAA battery pack works well.
Use a different power supply for the Arduino and connect all the grounds together.
I was given the specs for that micro servo motor. It draws up to about 300 mA.
The stall current for the SG90 servo is 650 +/- 80 mA.
With a resistor between GND and -.
With a resistor between GND and -.
No. Please don't make things up. Just follow instructions.
Do you need that potentiometer, though?
live_wire:
Do you need that potentiometer, though?
Only if you want a control of some sorts.
I am trying to make a fully autonomous robot. I am mounting my ultra-sonic sensor on the servo to move it around to detect objects. So, what is the best (and simplest) way to wire it up so that I control the servo only with my PWM pins? Where, if at all, would I need resistors?
live_wire:
I am trying to make a fully autonomous robot. I am mounting my ultra-sonic sensor on the servo to move it around to detect objects. So, what is the best (and simplest) way to wire it up so that I control the servo only with my PWM pins? Where, if at all, would I need resistors?
Then you'll need a lot more code than you've shown us so far. When you post your code we'll see what goes on.
BTW you don't drive servos from PWM pins if you have any sense. You use the Servo library which is made for the purpose. See Servo - Arduino Reference
Steve
Hi,
live_wire:
I am trying to make a fully autonomous robot. I am mounting my ultra-sonic sensor on the servo to move it around to detect objects. So, what is the best (and simplest) way to wire it up so that I control the servo only with my PWM pins? Where, if at all, would I need resistors?
Please write your code in stages, keeping each control aspect of your project as separate codes, until you have each aspct working, then combine them one at a time.
Each time getting the new code working BEFORE adding another bit.
So
Just write code to get your servo(s) working.
Just write code to control one motor then all your motors.
Just write separate codes for each of your input devices.
Each time getting the new code working BEFORE adding another bit.
It will make your coding more structured and easier to debug as you combine the parts.
Can you please tell us your electronics, programming, Arduino, hardware experience?
If you use the Servo library, you can use any digital pin, you are not restricted to the PWM designated pins.
Tom... 