Hi! I am starting a project with a robotic arm, which will consist of 4 servos. 3 of those which require from 4.8 to 6 amps, and another that uses 4 amps. I'll add the links for the servos, respectively:
What Arduino are you using? You don't normally need a driver for servos. If you use the Servo library the servos can be controlled from any digital pin.
Then all you need is a power supply to provide enough current (amps) at the correct voltage. What voltage are you planning to run the servos on? I'm not sure where you got those ratings from, particularly the smaller servo whose spec seems to says 2.1A-2.7A stall.
slipstick:
What Arduino are you using? You don't normally need a driver for servos. If you use the Servo library the servos can be controlled from any digital pin.
Then all you need is a power supply to provide enough current (amps) at the correct voltage. What voltage are you planning to run the servos on? I'm not sure where you got those ratings from, particularly the smaller servo whose spec seems to says 2.1A-2.7A stall.
Steve
Hi Steve!
I'm using an Arduino UNO R3 and I'll be applying 6V on the servos.
Also, I just saw that I used the wrong rating on the smaller servo. You are correct, it is 2.1A - 2.7A. I double checked the larger one on the description on Amazon and it specifies 4.5A - 6A.
To echo slipstick, you don't have to use a shield to drive servos. If you did need to for some reason, I'm not convinced that the Adafruit one could hack it - I don't see anything in their documentation that specifies maximum current.
Since that board can manage 16 servos, I'd expect that it can handle a minimum of 16A with quite some margin to spare. Whether the traces can manage 6A on one servo though, I'm not sure. If it can, I do note that you can daisy chain them, so it might be viable with two of them.
If you're doing a lot of calculation and need to offload the Servo piece from the Uno, rather than get servo driver boards, I'd just get a more capable micro controller.
Once you hit four servos, using the PCA9685 controller module is actually an extremely sensible way to do it as it requires no timing support from the Arduino. And of course, you may well wish to add more servos. The module connects to the I2C interface on the Arduino.
Vastly cheaper from Aliexpress!
But for anything other than the lightweight "SG90" type servos, you do not use the module to distribute power, you provide and wire power to the servos directly and connect only the control wires and ground to this module.
Hi, @chris1216, I think you have the thought that the load current is supplied to the servo via the signal pin.
The power for the servo is delivered by the power supply leads, the signal pin odes not need to supply much current at all, just a signal to control the servo's in built controller/driver.
Also realise if the servo is to hold a position, say 65degrees, and there is a load torque on the servo shaft, the servo will consume current to produce a torque to maintain that position.
