Not new to Arduino, but signed up due to a servo question I had to ask.
I've dug out a servo from my parts bin and tried running it as per multiple internet tutorials and the Servo library tutorial.
All the instructions have been followed to the letter.
HOWEVER...
When powered, the servo will immediately go to anti clockwise most position and then judder and shake.
I have tried controlling it with manual millis, servo write milliseconds, and the servo write functions.
None of these are working.
My Uno board is running at the right frequency, I've tried all the PWM pins for servo control, but I have no idea what is wrong with the servo.
The horn can be rotated slightly greater than 180°.
Is it possible for the electronics in a servo to be broken?
Simple servo test code you might use to test the servo.
// zoomkat 7-30-10 serial servo test
// type servo position 0 to 180 in serial monitor
// for writeMicroseconds, use a value like 1500
// Powering a servo from the arduino usually *DOES NOT WORK*.
String readString;
#include <Servo.h>
Servo myservo; // create servo object to control a servo
void setup() {
Serial.begin(9600);
myservo.attach(9);
}
void loop() {
while (Serial.available()) {
if (Serial.available() >0) {
char c = Serial.read(); //gets one byte from serial buffer
readString += c; //makes the string readString
delay(3);
}
}
if (readString.length() >0) {
Serial.println(readString);
int n = readString.toInt();
Serial.println(n);
myservo.writeMicroseconds(n);
//myservo.write(n);
readString="";
}
}
But to answer your question directly yes it is possible for the electronics to be broken but that usually means it doesn't work at all. And it is also possible for the feedback pot to be displaced...this is particularly likely if you have been turning the servo by hand against the electronics which also tends to damage the gearing.
With new micro servos now costing about $0.30 on Aliexpress I'd probably just throw it away and get a new servo unless it's something really special.
I took apart the servo, had a look at the gears (OK) but I am pretty sure the pot wasn't lined up properly with the gear that has the physical stops on it.
I then reassembled it with the gear lined up, which worked for a while before doing the same thing again.
Is that gear supposed to be glued to the pot shaft or anything?
