Absolute position 180-deg servo

Other Hardware Motors, Mechanics, Power and CNC
1

Hello, How can I set the absolute position of the 180-deg servo. I mean to write Servo.write(180) and the servo drive will move TO THE 180 degree position.
I wanna move it for example from 90 to 180 using absolute position

2

Try put in negative -180.

3

Will the servo turn -180 position with each command?

4

If you say 180 first and then say -180, the servo should return to its initial position.

5

If u want to mov to 90n just write 90, no?

6

Do you have a servo or do you have a continuous rotation "servo" ?

If the latter than it cannot be commanded to go to an absolute position as you can only control its speed and direction

If you have an actual servo as used in RC aircraft then be aware that not all of them can move through a range of 180 degrees no matter what you write to them

Please provide a link to the device

7

A test program:


/*
 Try this test sketch with the Servo library to see how your
 servo responds to different settings, type a position
 (0 to 180) or if you type a number greater than 180 it will be
 interpreted as microseconds(544 to 2400), in the top of serial
 monitor and hit [ENTER], start at 90 (or 1472) and work your
 way toward zero (544) 5 degrees (or 50 micros) at a time, then
 toward 180 (2400). 
*/
#include <Servo.h>
Servo servo;

void setup() {
  // initialize serial:
  Serial.begin(9600); // set serial monitor line ending to Newline
  servo.attach(9);
}
void loop() {
  // if there's any serial available, read it:
  while (Serial.available() > 0) {

    // look for the next valid integer in the incoming serial stream:
    int angle = Serial.parseInt(); 
    // look for the newline. That's the end of your
    // sentence:
    if (Serial.read() == '\n') {
    }
    angle = constrain(angle,0,180);
    servo.write(angle);
    Serial.print(angle);Serial.print("\t");
    Serial.println(servo.readMicroseconds());

  }
}
9

Running the Sweep example and reporting what the servo does would give valuable feedback as to the type of servo/“servo” you have and what it is capable of

10

That's how servos work. write(180) will move to a fixed position from wherever the servo is now.

The only thing to consider is that write(180) actually moves the servo to its MAXIMUM position. If it is only a 120 degree servo then it will move to 120, if it is a 270 degree servo then write(180) will move it to position 270.

Steve

11

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