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Electronics => Electronics => Topic started by: izua on February 27, 2008, 04:47:08 PM

Title: Servo output wheel spins out of center
Post by: izua on February 27, 2008, 04:47:08 PM
I've taken out the electronics of two servos. I've put grease on the reduction mechanism. But even before beeing hacked, one of the servo output wheel was spinning out of center. It's not that noticeable, but it makes a weird sound when I connect the horn. There is still some skreeching without the horn.

I drilled holes through a wheel (although, they were drilled badly): 2, further away from the centerand at fixed locations, on the wheel's diameter (so holes + center are colinear) put resistors through the holes and into the servo horn. The wheel was spinning terribly out of center.

The same thing happens on the "good" servo. I've checked the unhacked servos, and those, too, seem to be spinning a bit off the center.
What should I do? No tutorial ever mentions something about this problems.
Title: Re: Servo output wheel spins out of center
Post by: Ro-Bot-X on February 28, 2008, 11:48:02 AM
Looks like the mold for the servo case is bad. Those servos are horrible. Get a brand name servo instead and you will not have this problem. This is the reason no one mentions anything about this in the modding tutorials. Try to find GWS servos, they are powerfull and verry good quality and cheaper than Hitech or Futaba.
Title: Re: Servo output wheel spins out of center
Post by: airman00 on February 28, 2008, 07:25:15 PM
so GWS are good servos and work like Hitec ones, rite?

I also heard that Hitec owns GWS or something

P.S.

Sorry for slightly hijacking this thread , even though its a bit on topic
Title: Re: Servo output wheel spins out of center
Post by: Ro-Bot-X on February 29, 2008, 12:32:08 AM
GWS standard servos are a little bigger than Hitech, but also almost double the torque. I am talking about S03T 2BB. I have seen bipeds with these servos and they work nice. In my arm they also hold their positions nice. I am very happy with them. I plan to buy more to make a byped someday.
Title: Re: Servo output wheel spins out of center
Post by: airman00 on February 29, 2008, 12:35:00 PM
GWS standard servos are a little bigger than Hitech, but also almost double the torque. I am talking about S03T 2BB. I have seen bipeds with these servos and they work nice. In my arm they also hold their positions nice. I am very happy with them. I plan to buy more to make a byped someday.

Thanx for the input Ro-Bot -X


Next time i need servos, Ill check out the GWS ones
Title: Re: Servo output wheel spins out of center
Post by: Fredrik Andersson on February 29, 2008, 12:43:18 PM
You have my recommendations on GWS servos as well. The slightly larger size is the only problem I've encountered, but is not really a problem as i use custom brackets for my hexapod.
Title: Re: Servo output wheel spins out of center
Post by: Admin on March 03, 2008, 07:49:37 AM
Quote
GWS standard servos are a little bigger than Hitech, but also almost double the torque.
Thats because they operate at half the speed:
http://www.maximumrobotics.com/store/p/1029-S03T-2BB-Servo-w-JR-Connector.aspx

This is great for robot arms/legs, but bad for wheels.
Title: Re: Servo output wheel spins out of center
Post by: Mcrich113 on March 05, 2008, 12:03:32 AM
Hey guys!
      You really need beter servos, all electronics correspond with age, so how old are your servos?Some good stores and companies are advertised here, look at them.

thanks!Mcrich113 ;D