need to activate 4 servo motors based on load cell data

Projects General Guidance
1

Need to activate four servo motors based on load cell data for development of weight base grader.
I'm new for this for I tried my best and created a programme.
On LCD it showing the exact weight but the servo motors are getting fluctuations.
can you please help by checking the below mentioned programme..

#include <Servo.h>
#include <HX711_ADC.h>
#include <Wire.h>
#include <LiquidCrystal.h>
HX711_ADC LoadCell(3, 2);
Servo myservo1;
Servo myservo2;
Servo myservo3;
Servo myservo4;
float calibration_factor = 135; // this calibration factor is adjusted according to my load cell
float units;
float ounces;
LiquidCrystal lcd(12, 11, 7, 6, 5, 4);

void setup() {
Serial.begin(9600);
LoadCell.begin();
LoadCell.start(2000.10);
LoadCell.setCalFactor(399.30);
myservo1.attach(8); //servo pins digital
myservo2.attach(9);//servo pins
myservo3.attach(10);//servo pins
myservo4.attach(13);//servo pins
//scale.set_scale();
//scale.tare(); //Reset the scale to 0

//long zero_factor = scale.read_average(); //Get a baseline reading
//Serial.print("Zero factor: "); //This can be used to remove the need to tare the scale. Useful in permanent scale projects.
//Serial.println(zero_factor);
lcd.begin(16, 2);
}

void loop() {
LoadCell.update();
float i = LoadCell.getData();
Serial.println ("i");
lcd.setCursor(0, 0);
lcd.print("Weight[g]:");
lcd.setCursor(0, 1);
lcd.print(i);
// scale.set_scale(calibration_factor); //Adjust to this calibration factor

Serial.print("Reading: ");
//units = scale.getData(), 10;
if (i < 0)
{
i = 0.00;
}
ounces = i * 0.035274;
Serial.print(i);
Serial.print(" grams");
Serial.print(" calibration_factor: ");
Serial.print(calibration_factor);
Serial.println();
if (i >100 && i <105)
{
myservo1.write(180); // if weight is more than 100 gm then servo motor move 180 degree anti clockwise
delay(5); // waits 15ms for the servo to reach the position
myservo1.write(-180);
}
if (i > 105 && i <110) // if weight is more than 105 gm then servo motor move 180 degree clockwise
{
myservo2.write(180); // tell servo to go to position in variable 'pos'
delay(5); // waits 15ms for the servo to reach the position
myservo2.write(-180);
}
if (i > 110 && i <115) // if weight is more than 110 gm then servo motor move 180 degree clockwise
{
myservo3.write(180); // tell servo to go to position in variable 'pos'
delay(5); // waits 15ms for the servo to reach the position
myservo3.write(-180);
}
if (i > 115 && i <120) // if weight is more than 115 gm then servo motor move 180 degree clockwise
{
myservo4.write(180); // tell servo to go to position in variable 'pos'
delay(5); // waits 15ms for the servo to reach the position
myservo4.write(-180);
}
delay(5);
lcd.setCursor(0, 0);
{
lcd.print("Weight(g)="); // Weight print in lcd
lcd.println(i);
}
}

2

Start by Auto formatting your code in the IDE to improve its layout then posting it here using code tags (</> icon, top left of the edit window here) or Edit/Copy for forum in the IDE, to prevent the code being interpreted as HTML commands. Do you see the smiley in the code in your original post ?

As to your problem, I see this in your code (note what it looks like in code tags)

  if (i > 100 && i < 105)
  {
    myservo1.write(180);              // if weight is more than 100 gm then servo motor move 180 degree anti clockwise
    delay(5);                       // waits 15ms for the servo to reach the position
    myservo1.write(-180);
  }

The comments make no sense, but I know where they came from, and writing -180 to a servo is invalid as the range of values is 0 to 180. What are you trying to make the servo do at that point ? What type of servos do you have and how are they powered ?

3

This code looks as if you have deliberately designed the flutcuations

if (i >100 && i <105)
  {
      myservo1.write(180);              // if weight is more than 100 gm then servo motor move 180 degree anti clockwise
      delay(5);                       // waits 15ms for the servo to reach the position
      myservo1.write(-180); 
  }

Move the servo, wait 5 millisecs and then move it back. And note that your comment is wrong. (And as pointed out in Reply #2, -180 is wrong)

You need to provide a better description of what actually happens and what you want to happen that is different.

And I have no idea what "weight base grader" means.

...R

PS ... To make it easy for people to help you please modify your post and use the code button </>
codeButton.png

so your code looks like this

and is easy to copy to a text editor. See How to use the Forum

4

Thanks bob and robin for your immediate action,
If -ve angle is not considered, can you tell me how the motor comes to its original position after rotation of 180 with an example code if possible

5

RC control frames are 20ms long.

Nothing at all will happen in 5ms.

6

If -ve angle is not considered, can you tell me how the motor comes to its original position after rotation of 180 with an example code if possible

Take a look at the Sweep example, which judging by the comments in your code (which actually do not match the code),

    delay(5);                       // waits 15ms for the servo to reach the position

you already have

What type of servos do you have ? Are they actually servos or are they continuous rotation "servos" which are not really servos at all ?