
feroze
USA
Asked
— Edited
Hello,
I have a small arm on my robot and when it extends outward the servo makes a slight buzzing sound from the weight of the arm. Is this bad for the servo?
Also, I'm no expert.
I did add a helper spring to my High Power Servo. It's lifting about 15 lbs and it stopped buzzing.
Servos are loud because of their design. A servo is a little motor. And the little motor has gears. The gears add torque to the motor's output. If you turn the motor a few rotations, the output shaft of the servo will turn a tiny little bit. This allows the servo to move heavier objects with precision. The servo circuit knows what position the servo is in by a little potentiometer. When the output shaft moves, the potentiometer does also. The EZ-B sends a signal to the servo and tells it what position to hold the potentiometer in. When you apply load to the shaft, the potentiometer notices and sends a pulse to the motor. The motor moves to attempt and hold the position. The motor will move back and forth rapidly to hold the position.
And voila, your buzzing noise
If you have room in your robot, get some Dynamat off of eBay and give it a try.
Here's a video comparing accuracy but you can use this as a reference of what difference analog vs digital makes.
https://www.youtube.com/watch?v=ILKEAgL-a9w&feature=youtube_gdata_player
Here are two analog servos close up and you can hear about how much noise they make ( not much)
https://www.youtube.com/watch?v=uTi_U3ogIy4&feature=youtube_gdata_player
I can understand your concern , my hitec 5995 ltg servos make a loud buzzing that would drive me nuts even under the lightest load so I found they would not be what I want for my robots shoulders. I went with a analog servo and a gearbox to multiply the torque. You can usually search YouTube by model to see how a servo performs and sounds. Digital will always buzz at least a little and is part of how they work but a analog in some cases can make much less noise. Its all preference.