Hi guys, beginner with ardunio here and my problem is that I'm trying to control 4 servo motors with 4 10k potentiometers like this video: How to make a robot arm - Arduino | Acrylic Robot Claw Arm - YouTube I have assembled the robot arm the same way as the video, some parts are loose but I taped it together so it shouldn't be a problem. The only difference is that I use a breadboard instead.
When I connect 1 sg90 servo to a breadboard and try to control it with a 10k pot connected to the same breadboard powered by 9v battery connected directly to the arduino board exactly like this Arduino Tutorial: Servo Potentiometer Control - Beginner Project - YouTube everything goes perfectly fine but once I put the servo in the arm robot it goes just as well.
But then the problem starts when i connect 2 servos and 2 potentiometers on the same breadboard powered with the 9v battery directly to the arduino board, and put it in the arm robot, suddenly whenever i turn the potentiometer there's a delay and the orange light on the arduino board starts blinking then the servo turn.
My question is why when i put just only 2 servos into the arm robot and try to control it using 2 potentiometers, there's a delay and board orange light blinks WHEREAS when i take it out of the robot IT WORKS PERFECTLY FINE, when its not in the robot arm there's no orange light blinking all the servos move fine no delay whatsoever. I am so confused i have tried switching batteries and everything, all help would be very greatly appreciated.
If this is a PP3 battery intended for use in smoke alarms then it cannot supply enough current to run the Arduino for more than a few minutes, let alone 4 servos for the MeArm
I suspect that the Arduino is rebooting due to brownout when you take too much current from the battery
You need to use an external power supply capable of supplying the required current
Far more sensible.
But you have to connect it to the servo power connections, not the "barrel jack" on a UNO.
The "shield" on the video has a barrel jack that apparently powers the servos and UNO given a 5 V 2 A mains adapter. 6 V (or more) from four alkaline dry cells is too much for the Arduino, OK for the servos. four Ni-MH rechargeables would be OK for both.
I see, thank you so much for your response. It turns out i have been using the pp3 battery and the 9v dc adpater i meant is the same as the picture you sent.
I used 4 1.5v batteries (i think its not the rechargeable one) in series to power the 4 servos directly on another breadboard but the problem still persists. Theres 1 breadboard which i connect 4 potentiometers and then theres another breadboard that is only connected to the 4 servos powered by 4 batteries. i give power to the board with the pp3 battery through that dc adapter and connect the board to the breadboard with only potentiometers via the 5v pin on the Arduino.
I was thinking and is it possible that there is too much load on the servos as when in the MeArm it misbehaves but when it moves through air it does just fine.
So do i need batteries that have more amp like 2 amp while providing the same 6 volts for the servos and what would i need to power my potentiometers, would the pp3 battery be enough?
Another possibility is that the positive and negative wires from the battery holder is connected loosely, could loose connections also cause servos to delay?
Another thing is that i connected my servos to the non-pwm pins on the arduino uno could that also contribute to the problems? Also sorry for many questions, i really want to understand why it isnt working for me while it looks like it works perfectly fine for everyone else with minimal problems.
4xAA batteries cannot provide enough current for four servos. You need a 5 to 6V, 4 Ampere (or more) power supply for small (SG90) servos, and a 5 to 6V, 10 Ampere (or more) power supply for four of the larger (MG996R) types.
Breadboards are for low power logic circuits, and cannot handle the current required by motors and servos. The tracks will burn. Instead, use a servo power distribution PCB. Either buy one, or build one.
I found a 5v 10a power supply and I will be trying to use it with the pca9685. Is the label 10a just the capacity like how that's how many amperes it can deliver or does 10a mean it will deliver exactly 10a not the maximum is 10 amperes?
Is there also a difference in the labeling of power supply, in 1 power supply the label at the output is labeled as 5Vmax=10Amax but another power supply label is the same 5V=10A but with no max, is the meaning still the same?
Would putting too much amp like 10 amp into a capacitor of pca9685 explode it? As far as I can see the capacitor only has a max volt label of 5 volts but no amp max label.
Also, does anyone know the name of the adapter that turns DC barrel jack into positive and negative wires?
Almost all power supplies are rated for the DC voltage output they will provide, over a range of current. It's extremely unlikely that you have anything but that.
The capacitor doesn't care about the PS amperes available. There are ways you can destroy it (reversing the input voltage, for example), but PS current isn't one.
Adapter - try "5.5 mm 2.5 mm adapter" at amazon, and go from there.
C
(words added, corrected)
The power points (utility outlets) in my home are rated at 240 V 10 A. They are in effect, a "power supply". I can plug in an electric radiator (heater) to warm me up (it is winter here) with 2400 W as that is the rating.
But I plug in my Ikea 3 W LED lamp and switch it on. Does it draw then 2400 W since the power point is rated at ten Amps?
Thank you for everyone's help, I understand so much more abt electronics now. I have decided to buy a 5v 10amp power supply so ill have enough currents for my 4 servos and pca9685 to connect the power supply so my breadboard won't burn. Once again tysm for the help I wouldn't be able to understand this by myself lol, if I test it and all goes well ill mark solution.
But one (maybe last) question: what happens if I plug in 2 power supply at once, for example: I plug a 9v battery into my arduino uno and then I plug a 5v battery into pca9685, both arduino and pca9685 is connected by 5v and gnd pin. Will the volt and amp from 2 power supplies intervene with each other and cause some sort of problem?
Yep im using that kind of battery, sry i deleted the other reply i didn't know there was an edit button.
Why only use 5v to power the arduino tho, i thought the recommeded volt would be 7-12? When i search arduino recommended volt in ggl it says that any volt lower than 6 the 5v pin will supply less than 5v?
