Arduino Uno Servos

[Elijah5647]

Hi ALL

I am wondering can someone help me on where to plug the wires on my modified servo to the Arduino Uno. I have a seperate battery source for the servo but am a bit confused which wires go where??

Help please

[Joker94]

If you have a separate battery source for the servos i would recommend getting a plug so you can plug the battery into the power jack on the board. this will make sure you have common ground and in the long run will make it more portable.

I assume that you mean you have a battery source for the servos as you are currently using the USB to power the board?

there is a high possibility that you have spare power plug that will fit connected to an old charger or wall mate that you don't use any more. you can just snip it off and make a cable to connect the battery to the jack. if you dont they are only a dollar or two.

form there there is a pin out along where the power pins are that says Vin.  next to it are 2 GND pins. you just have to take a lead from the VIN pin and connect it to the positive servo wire and do the same for GND. and then take a wire from the digital pin that you want to use and connect it to the signal wire as you already know.

what are you using the servo for?( sensor scanning, robot propulsion)?

when working with digital signal like the PWM signal to control the servo it is important that there is a common ground between all devices being used.

[greasemonkey94]

like the previous post, common ground is important and up until recently i didnt know why,

its simple really, the red wire goes to +ve terminal of the battery and the black wire goes to ground of arduino,
-ve terminal of battery goes to ground of arduino(use a breadboard for this) and signal wire goes to a pin on
arduino with PWM output, you could put it on any digital pin and create software pwm, but the first one is simpler.

look at this ----->http://arduino.cc/en/Tutorial/Sweep

[Soeren]

Hi,

like the previous post, common ground is important [...]

Not just important, but absolutely necessary!

[Elijah5647]

@Joker64 How many servos could that battery take or should I use seperate batteries on each servo like I am now. I am using the normal Hitec 311.

I am using two servos for propulsion and one to scan with a sensor.

[Elijah5647]

Also, as well as my Ping sensor I want to connect some photo resistors from the $50 robot to it. Is this right, I connect the ground wire to GRD, the power to five volt and then do I connect the signal to a digital or analog.

Thanks for all your help, SOR is awesome

[Joker94]

a battery can take many servos, the reason i asked is if you were only using a micro servos to scan a sensor you could just power it from the USB as the power drain would be so low due to a very small load and a small servo.

the only thing that will effect the battery by adding more servos is the amount of time that charge will last. what is your battery? voltage, mAh rating, chemistry?

as for the sensors. most sensors will return a voltage as a reading, therefore you need to plug it into an analog port. then the micro controller takes that voltage reading and converts it into a digital value for the micro controller to understand, thus the saying ADC (analog to digital converter)

and what you said about power to 5v, GND to the GND and then the signal wire to one of the available analog pins.

[Admin]

Also, as well as my Ping sensor I want to connect some photo resistors from the $50 robot to it. Is this right, I connect the ground wire to GRD, the power to five volt and then do I connect the signal to a digital or analog.

To analog:
http://www.societyofrobots.com/schematics_photoresistor.shtml

Thanks for all your help, SOR is awesome