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Topics => Robotics => Topic started by: ATWindsor on Jun 19, 2019, 09:31 pm

Title: Servo is jumping on just some outputs.
Post by: ATWindsor on Jun 19, 2019, 09:31 pm
I have 7 simple servo motors connected to my arduino, i control them via telnet. They are running on an external 5V power supply. On some of the outputs, it works fine. (for instance 2 or 3), but if i try some others, like 7 or 8, it moves to the right place, but after that it starts "jumping back and forth" or "jittering" (not sure what the technical term is), and continues with this "forever", if i change around the motors, the result is the same, some outputs works fine, others not, apparently independent of which motor is connected. Any tips on how to troubleshoot this?
Title: Re: Servo is jumping on just some outputs.
Post by: PaulS on Jun 20, 2019, 12:00 pm
By "output" are you referring to values, as in position, or pin numbers, as in the servo attached to pin N jitters while the servo attached to pin M does not?
Title: Re: Servo is jumping on just some outputs.
Post by: wildbill on Jun 20, 2019, 03:24 pm
The vast majority of servo issues reported here turn out to be insufficient power. Having an external power supply is a good start, how much current can it provide? Also, what voltage is it actually providing when the servos are powered up?
Title: Re: Servo is jumping on just some outputs.
Post by: ATWindsor on Jun 23, 2019, 12:26 pm
By "output" are you referring to values, as in position, or pin numbers, as in the servo attached to pin N jitters while the servo attached to pin M does not?
Sorry for the late reply, I have been withhout internet som days. I am refereing to the pin numbers. Servo attached to pin 2 and 3 doesn't jitter, attached to pin 7 or 8 jitters.
Title: Re: Servo is jumping on just some outputs.
Post by: ATWindsor on Jun 23, 2019, 12:39 pm
The vast majority of servo issues reported here turn out to be insufficient power. Having an external power supply is a good start, how much current can it provide? Also, what voltage is it actually providing when the servos are powered up?
It can provide 6,5A the voltage is 5,6V with the Servos powered up.
Title: Re: Servo is jumping on just some outputs.
Post by: PaulS on Jun 24, 2019, 04:42 pm
Quote
Servo attached to pin 2 and 3 doesn't jitter, attached to pin 7 or 8 jitters.
If you have servos attached to pins 2, 3, 7, and 8, and you move the control wires around, does the jittering follow the pin? That is, if you have a servo connected to pin 2 that does not jitter, and you move it to pin 7, and move that servo to pin 2, which servo now jitters?
Title: Re: Servo is jumping on just some outputs.
Post by: ATWindsor on Jun 24, 2019, 06:39 pm
If you have servos attached to pins 2, 3, 7, and 8, and you move the control wires around, does the jittering follow the pin? That is, if you have a servo connected to pin 2 that does not jitter, and you move it to pin 7, and move that servo to pin 2, which servo now jitters?
Yes, the jitter follows the pin, not the motor.
Title: Re: Servo is jumping on just some outputs.
Post by: TomGeorge on Jun 29, 2019, 07:09 pm
Hi,
Welcome to the forum.


Can you please post your code?
What model Arduino are you using?


Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html  (http://forum.arduino.cc/index.php/topic,148850.0.html). Then look down to item #7 about how to post your code.
It will be formatted in a scrolling window that makes it easier to read.


Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?


Thanks.. Tom...