My UArm trembles / Burned servo!

after a long time of stop (1-2 months), i’ve powered on my uarm.
It now trembles, both when stopped and during movements.

It seems like all the steppers oscillante around a position.
I notice that powering on it, when it is far from the zero rotation position, the initial movement of rotation is discontinuous, and not always it succeed in recover the correct rotational zero position.

Sometimes, during the reaching of a position, it loses tension and I see the arm fall down. Then the arm returns quickly up and completes the movement.

What can it be happened?


I’ve found one servo (the rotary one) not working properly.
It burned out in short time.
After disconnecting it, the motion of other axis became stable and correct.

Now i have to replace the burned servo (US D150A).
Does anybody can suggest me where to buy it?
Where can i find the data sheet of the d150A?


hi guys, if you have any problem with the servos in uarm, please give an email and also with the video or picture of the problem. We will try to help you:)