I have replaced my HS-475HBs with HS-5645MGs and have noticed the 5645s produce a whining noise under certain loads, usually when holding a position. This is not a problem, but I was just wondering why the big difference between the HS-475HBs vs. HS-5645MGs ?
I have also noticed the 5645s are a lot smoother. Everything works fine otherwise. My guess is the higher resolution causes them to resonate where as the standard servo is a little sloppier with motor control.
Is that a whine or a singing sound? If you have a mass at the end of a beam, it can oscillate. I see this with occasionally with my HB-475s when the 'bot is up on “blocks”, and a leg is extended.
Alan KM6VV
You replaced an analog servo with a digital servo having 2x the torque output and a metal gear train. You can hear the PWM of the motor driver when it’s holding position under load.
I should say it’s more of a hum vs. a whine and it does oscollate sligtly when standing still.
That’s what I was thinking, that the PWM pulses were causing the motor to resonate a hum sound. The digital servos are nice and smooth and I am happy with that. When I used the standard servos, the legs would shake when moving to positions and it was usually the leg that was not planted on the ground when taking a step.
These servos do move about 130deg out of the box which is nice. I have put shoulder brackets on the brat and added a temporary “cannon arm” on the right side to get an idea of how it looks. I just don’t have enough SES brackets to make arms at this point so I made do with what I have. The addition of the shoulder brackets and three more servos adds quite a bit more weight to the brat and it will not stand un-powered because the hip servos have so much rearward weight to support that it causes it to want to rotate backwards.
Hi,
Yeah, it sounds like PWM hum. Not too loud I hope!
Alan KM6VV
