Robot arm servos

Good afternoon and sorry for my English,

I wanted to tell you about a problem I had with a robotic arm.

I followed the tutorial to create a robotic arm:, I connected all the components to the protoboard, I entered the code and I have installed the application. When I wanted to check if everything worked correctly I have seen that the servomotors (both full-turn and small ones), only vibrate a little and do not turn. They vibrate every time I give an imput.

The fact that they vibrate makes me think that everything is correctly connected. I tried disconnecting and connecting servomotors but nothing changes.

What can I do to fix it?

Thank you!


The same advice you have already received and choose to ignore: Directly connect the servos to a power supply instead of trying to power them through a breadboard.

You can, also, purchase a better quality breadboard.

Good afternoon. I have tried to connect one of the servos directly to the power supply and the result is the same. I attach an image of the connection that I have made (there are only 2 servos in the draw, and the white piece represents the bluetooth receiver)


Thank you and excuse the insistence.

As far as I see the servos are still connected to power through the breadboard.

Have you did any research into how much current your breadboard can handle?

By typing in the words "breadboard current" into a internet search engine should bring rather informative information on the current limitations of the breadboard.

The technical specifications of the Breadboard:

Matrix: 126 terminals with 5 separate points plus 4 horizontal bus lines (power lines) with 50 test points each.
Input voltage: 6.5-12V (DC) or USB power supply
Output voltage: 3.3V / 5V switchable
Maximum output current: <700 mA
Two roads have independent control and can be changed to 0V, 3.3V or 5V.

I tried connecting the 6 servos directly to the power supply. Now they no longer vibrate, they rotate but keep it under control.

Could it be that there was a problem with the connection of the Bluetooth HC-06? I have looked in a lot of places and I think that I’m well connected, but I’m not sure either.

Thank you!

How much stall current does your servos need?

Does the stall current exceed this:

Maximum output current: <700 mA

? Of course the number is for the entire breadboard, so each servo will, most likely, be able to get less current.

Good afternoon,

I have been looking for features and for the big servo the loss current is 2.5A and for the small ones it is 650 mA.

EDIT: I just modified the code and I have put a simple one to check the operation of the servomotors.

They all work correctly and execute the code, so I guess the problem will be exclusively with the bluetooth receiver.


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