Am I using a good servo? It does work but...

Projects Discussion and Showcase Robotics
1

Hi all, I have a servo controlled via 4 pushbuttons for positions (+ led position indicator).
Everything seems to work but the servo simply won't turn to the various position as supposed to.
It does indeed move, the 0 point seems to be at 92 degree and it's fine but I supposed it's limited.
I'm using an HENGE MD5924D.

My code

#include <Servo.h>

Servo myservo;

int p1 = 2;
int p2 = 3;
int p3 = 4;
int p4 = 5;

int led1 = 10;
int led2 = 11;
int led3 = 12;
int led4 = 8;

void setup() {

myservo.attach(9);

pinMode(2, INPUT);
pinMode(3, INPUT);
pinMode(4, INPUT);
pinMode(5, INPUT);
pinMode(led1, OUTPUT);
pinMode(led2, OUTPUT);
pinMode(led3, OUTPUT);
pinMode(led4, OUTPUT);
digitalWrite (led1, HIGH);
digitalWrite (led2, LOW);
digitalWrite (led3, LOW);
digitalWrite (led4, LOW);

}

void loop() {
int p1 = digitalRead(2);
int p2 = digitalRead(3);
int p3 = digitalRead(4);
int p4 = digitalRead(5);

if (p1 == HIGH) {
digitalWrite (led1, HIGH);
digitalWrite (led2, LOW);
digitalWrite (led3, LOW);
digitalWrite (led4, LOW);
myservo.write(92);
delay(1000); }

if (p2 == HIGH) {
digitalWrite (led1, LOW);
digitalWrite (led2, HIGH);
digitalWrite (led3, LOW);
digitalWrite (led4, LOW);
myservo.write(180);
delay(1000); }

if (p3 == HIGH) {
digitalWrite (led1, LOW);
digitalWrite (led2, LOW);
digitalWrite (led3, HIGH);
digitalWrite (led4, LOW);

myservo.write(0);
delay(1000); }

if (p4 == HIGH) {
digitalWrite (led1, LOW);
digitalWrite (led2, LOW);
digitalWrite (led3, LOW);
digitalWrite (led4, HIGH);
myservo.write(120);
delay(1000); }

}

I've read about continuos servo, winch servo...but I don't know if it's me doing it wrong or simply I need to replace that servo.

Thank you

EDIT: dss-m15s should be good in this case? it's a 270° servo and 270° is the max angle that my project need

2

pull down resistors on the buttons?

3

Have you tried calibrating your servos?

4

Servo button test code you might compare to your code.

//zoomkat servo button test 12-29-2011
// Powering a servo from the arduino usually *DOES NOT WORK*.

#include <Servo.h>
int button1 = 4; //button pin, connect to ground to move servo
int press1 = 0;
int button2 = 5; //button pin, connect to ground to move servo
int press2 = 0;
Servo servo1;

void setup()
{
  pinMode(button1, INPUT);
  pinMode(button2, INPUT);
  servo1.attach(7);
  digitalWrite(4, HIGH); //enable pullups to make pin high
  digitalWrite(5, HIGH); //enable pullups to make pin high
}

void loop()
{
  press1 = digitalRead(button1);
  if (press1 == LOW)
  {
    servo1.write(170);
  }    
  
  press2 = digitalRead(button2);
  if (press2 == LOW)
  {
    servo1.write(10);
  }
}