Servo HAT  - prevent servo twitching

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gozaro
 
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Servo HAT  - prevent servo twitching

Post by gozaro »

Hi,

I’m using Servo HAT for a project with servos. I have installed the Python libraries and everything is working fine, but when powering the Servo HAT the servo connect to him twitches a little bit moving the mechanism that the servo controls before is required.

How can I prevent this thing?

Salutations.

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adafruit_support_bill
 
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Re: Servo HAT  - prevent servo twitching

Post by adafruit_support_bill »

A 'twitch' on power up is typical behavior for any servo. It is unrelated to the HAT.

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gozaro
 
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Re: Servo HAT  - prevent servo twitching

Post by gozaro »

Yes you are right, but reading around internet seems that this is possible to prevent. I thought when I bought the product that this think was fixed.

Is there any easy way to prevent the servo twitching with the servo Hat? adding some components maybe?

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adafruit_support_bill
 
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Re: Servo HAT  - prevent servo twitching

Post by adafruit_support_bill »

The HAT prevents twitching of the servo when in use because it provides a much more stable signal than you can generate from a GPIO pin. But a twitch at power-up is purely a function of the way the servo's internal circuitry powers up. There is nothing the HAT can do to control that circuit until it is fully powered..

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gozaro
 
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Re: Servo HAT  - prevent servo twitching

Post by gozaro »

In my set up the servo is connected directly to the Servo Hat so is the Servo Hat the one powers up the servo.

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Re: Servo HAT  - prevent servo twitching

Post by adafruit_support_bill »

You provide power to the servo headers via the screw-terminals on the HAT. There is no active circuitry on the HAT to control the servo power - The HAT just generates the servo control pulses.

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