Author Topic: Quiet Servos  (Read 6586 times)

0 Members and 1 Guest are viewing this topic.

Offline Crunchy TheoryTopic starter

  • Full Member
  • ***
  • Posts: 80
  • Helpful? 0
  • "Well great is ok, but amazing would be great."
Quiet Servos
« on: November 09, 2010, 06:56:26 PM »
I tried searching the forums for this topic, but didn't find much.

I know I will probably get the answer that all servos make noise, but can anyone suggest specific servos that are built to be quieter? Or maybe suggest ways to cut down on noise (I've heard that wrapping them in foam can help). Or possibly if there's something to look for in a servo (like if higher quality, metal-geared ones typically produce less noise)?

Thanks in advance!
The only way to top an upright screen, keyboard, and mouse is to eliminate the need for humans to touch a PC at all. Oh, hello there Mr. Robot... what would I like you to do, you ask?

Offline Razor Concepts

  • Supreme Robot
  • *****
  • Posts: 1,856
  • Helpful? 53
Re: Quiet Servos
« Reply #1 on: November 09, 2010, 06:58:13 PM »
Digital servos constantly update themselves, often resulting in a high pitched noise, so stay away from them.

Offline waltr

  • Supreme Robot
  • *****
  • Posts: 1,936
  • Helpful? 98
Re: Quiet Servos
« Reply #2 on: November 09, 2010, 09:02:32 PM »
Most of the noise is from the speed reduction gears which are straight cut. The better quality servos do not make as much noise.
There are other gear box designs that use gears that are nearly silent but not available in a hobby servo format. They could be coupled with a encoder and feed-back motor controller but expect to pay.

Mounting the servos with vibration isolation helps to reduce the gear noise from being transmitted into the (Robot) frame. If not isolated the noise can be amplified.
In addition, burying the servo inside of a solid enclose can help contain the noise. Wrapping with foam also can help.

I have some Kraft (older RC equipment) KPS-30 servos that are quieter than the equivalent servos from other manufacturers. Their movement is also much smoother but they did cost over double the others.

Here is a link to Servo reviews but unfortunately it does not include noise.
http://www.servodatabase.com/

I am interested in hearing about the noise output of the currently available servos.

Offline Soeren

  • Supreme Robot
  • *****
  • Posts: 4,672
  • Helpful? 227
  • Mind Reading: 0.0
Re: Quiet Servos
« Reply #3 on: November 09, 2010, 10:46:48 PM »
Hi,

There are some low force servos using SMA wire as the "motor" (and so, doesn't make noise) and, depending on how much force you need, it would be easy to make a similar setup yourself.

Why do they need to be silent?
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

Offline photomark

  • Jr. Member
  • **
  • Posts: 44
  • Helpful? 0
Re: Quiet Servos
« Reply #4 on: November 11, 2010, 10:35:55 PM »
how quite do they need to be ?

Truth is you answered your own question and as it has been pointed out I dont think you will get what you want without paying big dollars and getting an industrial type of thing .

A far cheaper idea would be to shield the noise you are getting by putting the servo in a soundproof box .

Even that will still let some sound out and then there is also sound generated from the rest of the robot or whatever it is

Offline azy

  • Full Member
  • ***
  • Posts: 107
  • Helpful? 0
Re: Quiet Servos
« Reply #5 on: November 12, 2010, 11:30:26 PM »
jjjjzzzzz jjjzzzzz bzzzzzzz jeee jeee jeeez  :-\

I know the feeling.

Muscle Wire is good for very light operations, solenoids fitted with rubber dampers are almost silent.

You can lower the voltage on the servos or actuate them less aggressively. Ive owned dozens of cheap servos , messing around with RC cars and boats and they all buzzed and hummed to a noticeable extent.

You could open the servos and apply some really thick heavy grease, lithium grease, that will make a big difference to the noise levels.
Inside the servos are a normal tiny electric motor geared down 100 or so to 1
« Last Edit: November 14, 2010, 06:17:14 AM by azy »

Offline Crunchy TheoryTopic starter

  • Full Member
  • ***
  • Posts: 80
  • Helpful? 0
  • "Well great is ok, but amazing would be great."
Re: Quiet Servos
« Reply #6 on: November 17, 2010, 09:11:04 PM »
Thanks for all the advice guys. I suppose it doesn't really need to be silent, if you were wondering about it relating to a function of the robot.

As I have spent most of the time on the AI, I thought I'd devote a little more time to the engineering side. Since my girlfriend had been complaining about the noise it makes, I just picked that as the area I would focus on improving.
The only way to top an upright screen, keyboard, and mouse is to eliminate the need for humans to touch a PC at all. Oh, hello there Mr. Robot... what would I like you to do, you ask?

Offline Soeren

  • Supreme Robot
  • *****
  • Posts: 4,672
  • Helpful? 227
  • Mind Reading: 0.0
Re: Quiet Servos
« Reply #7 on: November 18, 2010, 06:07:22 PM »
Hi,

Since my girlfriend had been complaining about the noise it makes, I just picked that as the area I would focus on improving.
Hint: Earplugs are waaay cheaper than new servos - or if she's a good cook, buy her an MP3 player and some of her favorite music  ;D

A slightly larger DC motor with a good quality gearbox will be much quieter - and the sound is not as harsh as the servos.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

Offline Admin

  • Administrator
  • Supreme Robot
  • *****
  • Posts: 11,658
  • Helpful? 169
    • Society of Robots
Re: Quiet Servos
« Reply #8 on: November 21, 2010, 07:53:25 PM »
Most servos are designed to be dirt cheap, making huge sacrifices in noise, efficiency, and lifespan to keep the costs low. Blame on the fact that people only buy servos based on output torque and price, and lack of datasheets :P

If you want a quick 'solution', get some servo grease and rub it around the gears. It'll reduce the noise a bit.

Beyond that, you'd have to buy expensive quality servos or make your own to get something quieter.

Offline SquidBot

  • Beginner
  • *
  • Posts: 1
  • Helpful? 0
Re: Quiet Servos
« Reply #9 on: December 11, 2011, 05:41:14 PM »

Beyond that, you'd have to buy expensive quality servos or make your own to get something quieter.

I'm looking for the high quality servos you mention without luck.  What is a brand or outlet I can search for?

 


Get Your Ad Here