The better question to ask is how you would power 4 MG996R servo motors with a pca9685 driver, I am currently trying to work on a robotic claw and im using a nema 17 stepper and 3 Mg996r servo motors. I looked online (and with help from ai) and it told me i would need to find a power supply capable of giving me the stall current and voltage, this means 4x 6v, 2.5A = 24V and 10A minimum, is there anyway i can do this project without having to find a power supply? Is there any batteries or anything else i can do? It seems really unrealistic that we can have Rc cars and all these other robots that run on batteries whilst this one arm requires a beast of a battery.
No, it means 6V at 10A minimum. RC vehicle hobby shops sell suitable 6V NiMH battery packs.
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Why does the amperage multiply but not the required voltage?
The servos run on 6V and are connected in parallel, so the current adds.
Or you could use four 6V power supplies, one for each servo.
Don't forget to connect all the grounds.
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So the pca9685 driver connects all motors in series and that means the amperage increases but the voltage is shared
I recommend you spend some time with basic electronics. Here is a link to start with: https://www.electronicsandyou.com/basic-electronics.html You will also find the Arduino Cookbook is a great read and introduction to the world of Arduino.
On the PCA9685 boards, the servos are powered in parallel.
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Got it thank you
DroneBotWorkshop covers servo motors and the PCA9685 in text and video.
Got it thank you all for the help!
That is just how it works. Covered in first year of study.
Because the cars don't have those servos.
I have one more question as well, in terms of powering this project, I dont know what type of battery i should use and for what motor, i was thinking about using a battery for my nema 17 motor but i have no clue what battery would work best. What do yall recommend i do?
See post #2.
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Do we know something about your nema17 stepper (except that it has nema17 mount)?
And about the stepper driver?
If I have to guess, you need 12V battery for that.
Also, why you need to use pca9685 for your servos?
Well you said 6V NiMH battery, does the Ah of the battery matter then? Like if i have a battery that is 6v but only 2200mah would that be enough for the motors?
Im connecting 3 servos to the driver to control them with one slot on the arduino, and the nema 17 is 12v and 1.6 to 1.8 amps per step
So instead of 3 pins you prefer I2C board?
And what stepper driver you use?
Yes. Both for the max current draw and for the battery life.
Let's say you have heavy load on servos and they draw 1A each, 3A in total.
So you need battery that can supply that safely. For NiMh battery it means really big one.
Better to go with 2S Lifepo4 battery, they have much higher allowed current draw.
So i am using the a4988 stepper driver and i think after reading and reaserching that the pca9685 allows for the motors to wired in parallel and is easier to control. Do you recommend i do somethig else? Ive seen some videos on other people building robotic arms and claws and they all use the pca9685 stepper driver with mg996r motors