I am trying to build a Bluetooth RC car using an arduino nano. For power supply I use 6 1.5 V batteries both for the board and the 2 servos. The motor has an other 2 batteries for power supply. This is about the maximum I can fit inside the car.
Now my problem is that the board cannot supply the two servos. As soon as I ask for a movement, the voltage gets down and the board resets.
Now I read on that forum that external power supply is recommended for the servos. But I have a small robot using 4 servos at a time powered by an arduino nano, same model, with no trouble. It is power by 4 1.5 V batteries. I have bought the thing, thought so it has a kind of stabilized input power supply through LEDs and capacities.
Would you know how to build such a stabilized power supply for two (micro) servos ? Would a LED + resistance parrallel to a capacity do the trick ? And if yes, how to size the resistance and the capacity ?
How do you have it hooked up? What are the part numbers and specs?
Your power supply probably isn't the problem. It sounds like you're running power through the Nano for no reason.
OK, thanks for the interest. here are my settings :
I use 6x1.5 rechargeable batteries plug to a breadboard + and - lines.
I connect the arduino nano Vin to the +, the GND to the -
I connect the servos + and - to the + and - of the breadboard (not the arduino)
I connect the signal wire of the servos to digital output 3 and 6
when I execute the "sweep" example from the arduino IDE for 1 servo : OK
when I execute the "sweep" example and copy it fior the second servo : the board keeps on shutting down. I tried switching the servos, same problem.
And when I connect the servos to the +/- of the breadboard, the tension difference gets down. is that normal ?
It sounds like there is resistance between the battery and the Arduino / servo power interface.
Try testing by giving the Arduino a separate power supply with a common GND.
And with the single power supply try testing by connecting the servo power and GND more directly to the battery.
I tested the separate power supply with common GND : it works. The "+" potential drops down to 3 V though while it starts at 9V. So OK, I guess I have a resistance between my batteries and the breadboard.
But how to decrease it ? I use a battery case I recycled from a HITEC radio emmetter and additional wires... I will see if I can get an other battery case. Do you think it can be as simple as that ? How to perform a "clean" connection between batteries and the breadboard ? Do you have advices ?
Sorry. Without seeing the actual stuff (and not just pictures of it) I can't make any suggestions beyond ensuring that all the contacts are clean and any joints (soldered or crimped) are in good condition.
OK, after a bit a seraching I think I found the problem : for some reasons, one type of the rechargeable batteries I am using has a voltage getting down to 0.5 V when delivering current.
I think this explains the multiple switch off /switch on. I will buy new ones and see if it fixes the problem.
